SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

Under the Securities Exchange Act of 1934

Affinity Gaming

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

Not Applicable

(CUSIP NUMBER)

Thomas Surgent, Chief Compliance Officer

Highland Capital Management, L.P.

300 Crescent Court, Suite 700

Dallas, Texas 75201

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

May 29, 2013

(Date of event which requires filing of this statement)

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If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g) check the following box.  x

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (the “Act”), or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act.

SCHEDULE 13D

This Schedule 13D (this “Schedule 13D”) is being filed on behalf of Highland Capital Management, L.P., a Delaware limited partnership (“Highland Capital”), Strand Advisors, Inc., a Delaware corporation (“Strand”), and James D. Dondero (collectively, the “Reporting Persons”).

James D. Dondero is the President of Strand. Strand is the general partner of Highland Capital. Highland Capital is the investment advisor to certain private investment funds (collectively, the “Private Funds”). This Schedule 13D relates to Common Stock, $0.001 par value per share (the “Common Stock”), of Affinity Gaming, a Nevada corporation (the “Issuer”), held by the Private Funds. The Reporting Persons previously reported their beneficial ownership on a Schedule 13G that was filed with the Securities and Exchange Commission on February 28, 2011 and Amendment No. 1 thereto filed on February 14, 2013.

Securities acquired: Common Stock, $0.001 par value per share (the “Common Stock”).

Issuer: Affinity Gaming

3755 Breakthrough Way, Suite 300

Las Vegas, Nevada 89135

(a) This Schedule 13D is filed by and on behalf of each of the following persons (collectively, the “Reporting Persons”): (i) Highland Capital Management, L.P., a Delaware limited partnership (“Highland Capital”), (ii) Strand Advisors, Inc., a Delaware corporation (“Strand”), and (iii) James D. Dondero.

Each of the Reporting Persons declares that neither the filing of this Schedule 13D nor anything herein shall be construed as an admission that such person is, for the purposes of Section 13(d) or 13(g) of the Securities Exchange Act of 1934, as amended (the “Act”), or any other purpose, the beneficial owner of any securities covered by this statement.

Each of the Reporting Persons may be deemed to be a member of a group with respect to the Issuer or securities of the Issuer for the purposes of Section 13(d) or 13(g) of the Act. Each of the Reporting Persons declares that neither the filing of this Schedule 13D nor anything herein shall be construed as evidence that such person is, for the purposes of Section 13(d) or 13(g) of the Act or any other purpose, (i) acting (or has agreed or is agreeing to act together with any other person) as a partnership, limited partnership, syndicate or other group for the purpose of acquiring, holding or disposing of securities of the Issuer or otherwise with respect to the Issuer or any securities of the Issuer or (ii) a member of any group with respect to the Issuer or any securities of the Issuer. See additional information in Item 4 relating to the Reporting Persons’ potential membership in a group, which is incorporated herein by reference.

(b) The address of the principal business office of each of the Reporting Persons is 300 Crescent Court, Suite 700, Dallas, Texas 75201.

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(c) The principal business of Highland Capital, a registered investment adviser, is acting as investment adviser and/or manager to other persons, including the Private Funds. Highland Capital may be deemed to beneficially own the shares of Common Stock owned and/or held by and/or for the account of and/or for the benefit of the Private Funds. The principal business of Strand is serving as the general partner of Highland Capital. Strand may be deemed to beneficially own shares owned and/or held by and/or for the account of and/or for the benefit of Highland Capital. The principal business of Mr. Dondero is serving as the President of Strand. Mr. Dondero may be deemed to beneficially own shares owned and/or held by and/or for the account of and/or for the benefit of Strand.

(d) During the last five years, none of the Reporting Persons, nor, to the knowledge of the Reporting Persons, any of the persons controlling the Reporting Persons, or the directors or executive officers of Strand, has been convicted in a criminal proceeding in either case of the type specified in Items 2(d) or (e) of Schedule 13D.

(e) During the last five years, none of the Reporting Persons, nor, to the knowledge of the Reporting Persons, any of the persons controlling the Reporting Persons, or the directors or executive officers of Strand, was a party to a civil proceeding in either case of the type specified in Items 2(d) or (e) of Schedule 13D.

(f) The citizenship of Mr. Dondero is the United States. Highland Capital and Strand are Delaware entities.

The Private Funds acquired the shares of Common Stock through a reorganization in a bankruptcy proceeding in which the Private Funds exchanged notes in the predecessor with a par value of $77,515,750 for Common Stock and a new term loan, which was subsequently repaid.

In order to provide the Issuer with the opportunity to evaluate strategic alternatives for the benefit of all stockholders of the Issuer, the Reporting Persons, entered into an agreement, dated May 29, 2013, (the “Stockholder Agreement”), with certain other shareholders (the “Other Holders”). The Stockholder Agreement is filed herewith as Exhibit 99.2 and incorporated herein by reference. Because of the relationship between the Reporting Persons and the Other Holders as a result of the Stockholder Agreement, the Reporting Persons and the Other Holders may be deemed to constitute a “group” within the meaning of Section 13(d)(3) of the Act, and such group may be deemed to beneficially own the 10,243,320 shares of Common Stock held in the aggregate by the Reporting Persons and the Other Holders, constituting approximately 50.5% of the 20,268,339 outstanding shares of Common Stock. The Reporting Persons expressly disclaim, however, beneficial ownership of the 8,577,862 shares of Common Stock beneficially owned by the Other Holders. Information with respect to the Other Holders is or may be available in schedules that have been or may be filed by such Other Holders pursuant to Regulation 13D-G under the Act, as such schedules may be amended from time to time.

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The Private Funds purchased the Common Stock of the Issuer based on the belief that such securities, when purchased, were undervalued and represented an attractive investment opportunity. Although the Reporting Persons have no specific plan or proposal to acquire or dispose of the Common Stock of the Issuer, consistent with their investment purpose, the Reporting Persons at any time and from time to time may acquire additional Common Stock or dispose of any or all of their Common Stock depending upon an ongoing evaluation of the investment in the Common Stock, prevailing market conditions, other investment opportunities, liquidity requirements of the Reporting Persons and/or other investment considerations.

The purpose of the acquisition of the Common Stock of the Issuer was for investment, and the acquisition of the Common Stock of the Issuer was made in the ordinary course of business and was not made for the purpose of acquiring control of the Issuer.

Also, consistent with the investment purpose, the Reporting Persons may engage in communications with one or more shareholders of the Issuer, one or more officers of the Issuer and/or one or more members of the board of directors of the Issuer and/or one or more representatives or regulators of the Issuer regarding the Issuer, including, but not limited to, its operations. The Reporting Persons may discuss ideas that, if effected, may result in any of the following: the acquisition by persons of additional shares of Common Stock of the Issuer, an extraordinary corporate transaction involving the Issuer and/or changes in the board of directors or management of the Issuer.

Except to the extent the foregoing may be deemed a plan or proposal, the Reporting Persons have no plans or proposals which relate to, or could result in, any of the matters referred to in paragraphs (a) through (j), inclusive, of the instructions to Item 4 of the Schedule 13D. The Reporting Persons may, at any time and from time to time, review or reconsider their position and/or change their purpose and/or formulate plans or proposals with respect thereto.

(a) As of May 29, 2013, (i) Highland Capital may be deemed to beneficially own 1,665,458 shares of Common Stock, which represents approximately 8.2% of the outstanding Common Stock; (ii) Strand may be deemed to beneficially own 1,665,458 shares of Common Stock, which represents approximately 8.2% of the outstanding Common Stock; and (iii) James D. Dondero may be deemed to beneficially own 1,665,458 shares of Common Stock, which represents approximately 8.2% of the outstanding Common Stock. In the event that the Reporting Persons were deemed to have formed a group with the other Agreeing Stockholders, such group would beneficially own 10,243,320 shares of Common Stock, which represents approximately 50.5% of the outstanding Common Stock.

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(b)

In the event that the Reporting Persons were deemed to have formed a group with the Other Holders, such group would have shared voting and dispositive power over 10,243,320 shares of Common Stock, which represents approximately 50.5% of the outstanding Common Stock.

(c) No transactions in the Issuer’s securities were effected during the past 60 days by the Reporting Persons.

(d) No person other than the Reporting Persons is known to have the right to receive, or the power to direct the receipt of dividends from, or proceeds from the sale of, the Common Stock.

(e) Not applicable.

The responses to Item 4 are incorporated herein by reference.

Other than as described herein, there are no contracts, arrangements, understandings or relationships among the Reporting Persons, or between the Reporting Persons and any other person, with respect to the securities of the Issuer.

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Signatures

After reasonable inquiry and to the best of their knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: June 6, 2013

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Exhibit 99.1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, the undersigned agree to the joint filing on behalf of each of them of a Statement on Schedule 13D (including any and all amendments thereto) with respect to the Common Stock, $0.001 par value per share, of Affinity Gaming, and further agree that this Joint Filing Agreement shall be included as an Exhibit to such joint filings.

The undersigned further agree that each party hereto is responsible for the timely filing of such Statement on Schedule 13D and any amendments thereto, and for the accuracy and completeness of the information concerning such party contained therein; provided, however, that no party is responsible for the accuracy or completeness of the information concerning any other party, unless such party knows or has reason to believe that such information is inaccurate.

This Joint Filing Agreement may be signed in counterparts with the same effect as if the signature on each counterpart were upon the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of June 6, 2013.

Exhibit 99.2

STOCKHOLDERS AGREEMENT

This AGREEMENT, dated as of May 29, 2013 (this “Agreement”), is made by and between each of the entities listed on Exhibit A attached hereto (each such entity and any other person who becomes bound by this Agreement as contemplated by clause (a) of Section 1 hereof, a “Stockholder” and collectively, the “Stockholders”).

WHEREAS, as of the date hereof, each Stockholder is the beneficial owner (as defined under Rule 13d-3 of the Securities Exchange Act of 1934, as amended) of such number of shares of common stock, par value $0.001 per share (the “Shares”) of Affinity Gaming (the “Company”) as are set forth opposite such Stockholder’s name on Exhibit A attached hereto (the “Currently Owned Shares” and, together with such additional Shares as such Stockholder acquires beneficial ownership of after the date hereof, the “Owned Shares”); and

WHEREAS, the Stockholders wish to provide the Company with the opportunity to evaluate strategic alternatives for the benefit of all stockholders of the Company.

NOW, THEREFORE, in consideration of the foregoing and the representations, warranties, covenants and agreements set forth herein, and intending to be legally bound hereby, the parties hereto agree as follows:

1. Restrictions on Transfer. During the Term (as defined in Section 4 hereof), each Stockholder shall not, directly or indirectly, sell, transfer, pledge, encumber, assign, distribute, gift or otherwise dispose of (each, a “Transfer”), or enter into any agreement, arrangement or understanding (whether or not in writing) to Transfer, any of such Stockholder’s Owned Shares, unless: (a) the person or entity to whom such Owned Shares would be Transferred has executed and delivered to each Stockholder, with respect to all Owned Shares subject to such Transfer, an undertaking in the form attached hereto as Exhibit B (and, to the knowledge of proposed transferring Stockholder, the representations and warranties of such person contained therein are true); (b) such Transfer is made pursuant to a transaction, approved by the Company’s board of directors, for the sale of all or substantially all of the Shares or assets of the Company; or (c) such Transfer is approved by the holders of a majority of the Owned Shares held by Stockholders other than the proposed transferor after not less than two (2) business days’ notice of the proposed Transfer to each other Stockholder.

2. No Voting Agreements. Each Stockholder hereby represents, warrants and agrees that such Stockholder (a) has not entered into, and shall not enter into during the Term, any agreement or arrangement with any other person with respect to voting (or acting by consent in writing in lieu of voting) such Stockholder’s Owned Shares, and (b) has not entered into any agreement or knowingly taken any action (and shall not during the Term enter into any agreement or knowingly take any action) that would make any the representation and warranty of such Stockholder contained in Section 3(b) herein untrue or incorrect in any material respect or have the effect of preventing such Stockholder from performing any of such Stockholder’s material obligations under this Agreement.

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3. Representations and Warranties of the Stockholders. Each Stockholder represents and warrants as follows:

(a) As of the date hereof, (1) such Stockholder is the beneficial owner of the Currently Owned Shares; (2) the Currently Owned Shares constitute all of the Shares beneficially owned by such Stockholder; and (3) such Stockholder does not hold any options, warrants or other rights to purchase Shares or securities of the Company or any other securities convertible into or exercisable or exchangeable for Shares or securities of the Company.

(b) Such Stockholder has and (except as otherwise expressly provided by this Agreement) will have at all times until the termination of this Agreement sufficient rights and powers over the voting and disposition of the Owned Shares with respect to the matters set forth in this Agreement and to agree to all of the matters set forth in this Agreement, in each case with respect to all of the Owned Shares, with no other limitations, qualifications or restrictions on such rights, subject to applicable federal securities laws and the terms of this Agreement.

4. Term and Termination.

(a) Unless earlier terminated pursuant to paragraph (b) below, the term of this Agreement (the “Term”) shall be a period of six (6) months from the date hereof.

(b) This Agreement:

(1) may be terminated by Stockholders representing two-thirds of the aggregate number of Owned Shares held by all of the Stockholders bound by this Agreement by written notice to each other Stockholder delivered not less than two (2) business days prior to such termination;

(2) shall terminate automatically if the Company becomes subject to a binding and enforceable rights agreement substantially similar to the Rights Agreement, dated December 21, 2012, between the Company and American Stock Transfer & Trust Company, LLC, as rights agent, and within forty five (45) days thereafter such rights agreement has not become subject to any challenge in a court of competent jurisdiction;

(3) may be terminated at any time by any Stockholder as to itself (but not any other Stockholder) by written notice delivered to each other Stockholder following the occurrence of a Regulatory Event with respect to such first Stockholder; and

(4) may be terminated at any time by any Stockholder by written notice delivered to each other Stockholder if any other Stockholder has delivered a notice of termination in accordance with clause (3) above.

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“Regulatory Event” means, with respect to any Stockholder, (i) receipt by such Stockholder of notice from any casino or gaming regulatory authority of competent jurisdiction over the Company, any of its affiliates or any of the operations of the Company or any of its affiliates that, as a result of such Stockholder being bound by this Agreement, such Stockholder is required to obtain a license, permit, approval, waiver or finding of suitability that such Stockholder does not already have, (ii) such Stockholder shall have consulted with gaming counsel and such counsel shall have attempted and been unsuccessful in dissuading the applicable authority from such view and (iii) such Stockholder shall have determined that it no longer wishes to be bound by this Agreement.

(c) Any termination of this Agreement shall be without prejudice to liabilities arising hereunder before such termination of this Agreement.

5. Miscellaneous.

(a) Entire Agreement; No Third Party Beneficiaries. This Agreement, (1) constitutes the entire agreement and supersedes all prior agreements and understandings, both written and oral, between the parties with respect to the subject matter hereof and thereof and (2) is not intended to confer upon any person or entity other than the parties hereto and thereto any rights or remedies hereunder.

(b) Expenses. All costs and expenses incurred in connection with this Agreement and the transactions contemplated hereby shall be paid by the party incurring such expenses.

(c) Assignment. Except as permitted in Section 1 hereof, neither this Agreement nor any rights, interests or obligations hereunder, shall be assigned, in whole or in part, by any party hereto by operation of law or otherwise without the prior written consent of the other parties hereto. Subject to the preceding sentence, this Agreement will be binding upon, inure to the benefit of, and be enforceable by, the parties and their respective successors and assigns.

(d) Amendment and Modification. This Agreement may be amended, modified and supplemented in any and all respects, but only by a written instrument signed by all of the parties hereto expressly stating that such instrument is intended to amend, modify or supplement this Agreement.

(e) Waiver. The failure of either party to this Agreement to assert any of its rights under this Agreement or otherwise shall not constitute a waiver of those rights.

(f) Notices. All notices and other communications hereunder shall be in writing and shall be deemed given if mailed, delivered personally, telecopied (which is confirmed) or sent by an overnight courier service, such as Federal Express, to the parties at the address set forth on the signature page to this Agreement (or at such other address for a party as shall be specified by like notice).

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(g) Severability. Any term or provision of this Agreement that is held by a court of competent jurisdiction or other authority to be invalid, void or unenforceable in any situation in any jurisdiction shall not affect the validity or enforceability of the remaining terms and provisions hereof or the validity or enforceability of the offending term or provision in any other situation or in any other jurisdiction. If the final judgment of a court of competent jurisdiction or other authority declares that any term or provision hereof is invalid, void or unenforceable, the parties agree that the court making such determination shall have the power to reduce the scope, duration, area or applicability of the term or provision, to delete specific words or phrases, or to replace any invalid, void or unenforceable term or provision with a term or provision that is valid and enforceable and that comes closest to expressing the intention of the invalid or unenforceable term or provision.

(h) Specific Performance. In addition to any remedies available at law or otherwise, each party shall be entitled to equitable relief, including specific performance, in the event of any breach or threatened breach of this Agreement.

(i) Governing Law; Jurisdiction. (1) This Agreement shall be governed by and construed in accordance with the laws of the State of New York without giving effect to the principles of conflicts of law thereof.

(2) To the fullest extent permitted by applicable law, each party hereto (i) agrees that any claim, action or proceeding by such party seeking any relief whatsoever arising out of, or in connection with, this Agreement or the transactions contemplated hereby shall be brought only in the United States District Court for the Southern District of New York or any New York State court, in each case, located in the Borough of Manhattan and not in any other State or Federal court in the United States of America or any court in any other country, (ii) agrees to submit to the exclusive jurisdiction of such courts located in the Borough of Manhattan for purposes of all legal proceedings arising out of, or in connection with, this Agreement or the transactions contemplated hereby, (iii) waives and agrees not to assert any objection that it may now or hereafter have to the laying of the venue of any such proceeding brought in such a court or any claim that any such proceeding brought in such a court has been brought in an inconvenient forum, (iv) agrees that mailing of process or other papers in connection with any such action or proceeding in the manner provided in Section 5(f) (Notices) or any other manner as may be permitted by law shall be valid and sufficient service thereof and (v) agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by applicable law.

(j) Descriptive Headings. The headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation of this Agreement.

(k) Counterparts. This Agreement may be executed in two or more counterparts, all of which shall be considered one and the same agreement and shall become effective when two or more counterparts have been signed by each of the parties and delivered to the other parties.

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(l) Certain Regulatory Matters. Each Stockholder (other than SPH Manager, LLC), by its execution and delivery of this Agreement and notwithstanding its acknowledgements and agreements set forth herein, does not intend to alter its current passive investor status relative to its Currently Owned Shares. As a result, each such Stockholder intends to exercise its right to terminate this Agreement as to itself pursuant to Section 4(b)(3) immediately upon occurrence of a Regulatory Event with respect to such Stockholder. All agreements of a Stockholder herein are made subject to applicable gaming laws and regulations and interpretations of any applicable gaming regulatory authority.

[Signature page follows.]

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IN WITNESS WHEREOF, each of the parties has caused this Agreement to be duly executed as of the day and year first above written.

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EXHIBIT A

BENEFICIAL OWNERSHIP OF SHARES

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EXHIBIT B

FORM OF UNDERTAKING OF STOCKHOLDER TRANSFEREE

This UNDERTAKING (the “Undertaking”) is executed as of [DATE], by [NAME OF TRANSFEREE] (the “Transferee”).

WHEREAS, the Transferee wishes to acquire [—] shares (the “Transferred Shares”) of common stock, par value $0.001 per share (the “Common Stock”), of Affinity Gaming, a Nevada corporation (the “Company”), from [NAME OF SELLLING ENTITY] (the “Seller”); and

WHEREAS, the Seller is party to that certain Agreement, dated as of May [     ], 2013, by and between certain holders of Common Stock (the “Agreement”), a copy of which has been provided to the Transferee.

NOW, THEREFORE, in consideration of the foregoing, and intending to be legally bound hereby, the Transferee hereby agrees as follows:

1. Representation and Warranty of Transferee. The Transferee hereby represents and warrants to the Seller and each other Stockholder (as defined in the Agreement) that, after consummation of the acquisition of the Transferred Shares, the Transferee will not beneficially own (as defined in Section 78.414 of the Nevada Revised Statutes) more than the greater of (a) fifteen percent (15%) of the number of outstanding shares of Common Stock (based on the number of such outstanding shares last publicly reported by the Company) and (b) the number of shares of Common Stock beneficially owned as of the date hereof (without giving effect to the proposed Transfer of the Transferred Shares) by the largest holder of such shares (based on filings with the Securities and Exchange Commission), but excluding for the avoidance of doubt shares of Common Stock that may be deemed to be beneficially owned as a result of being (or becoming) bound by the Agreement.

2. Undertaking. The Transferee (a) hereby agrees to be bound by and comply with the provisions of Section 1 and Section 2 of the Agreement as if the Transferee were a party thereto and (b) acknowledges and agrees that this Undertaking is for the benefit of, and may be enforced by, each Stockholder.

IN WITNESS WHEREOF, the Transferee has caused this Undertaking to be duly executed as of the day and year first above written.

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