UNITED STATES
                         SECURITIES EXCHANGE COMMISSION
                             Washington, D.C. 20549

- -------------------------------------------------------------------------------


                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934
                                (Amendment No. 1)*

                         AMERICAN CAPITAL AGENCY CORP.
              ----------------------------------------------------
                                (Name of Issuer)


                          Common Stock, par value $0.01
                   --------------------------------------------
                         (Title of Class of Securities)


                                    02503X105
                             -----------------------
                                 (CUSIP Number)


                                  December 31, 2008
                               -----------------------
             (Date of Event which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

                              [ ]   Rule 13d-1(b)

                              [X]   Rule 13d-1(c)

                              [ ]   Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

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 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).


                          Continued on following pages
                               Page 1 of 14 Pages




                                 SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 2 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).

         SAB CAPITAL PARTNERS, L.P.
.................................................................................

2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         Delaware
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         PN



                                  SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 3 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).

         SAB CAPITAL PARTNERS II, L.P.
.................................................................................

2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         Delaware
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         PN



                                  SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 4 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).


         SAB OVERSEAS MASTER FUND, L.P.
.................................................................................

2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         Cayman Islands
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         PN



                                  SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 5 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).


         SAB CAPITAL ADVISORS, L.L.C.
.................................................................................

2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         Delaware
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         OO



                                  SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 6 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).


         SAB CAPITAL MANAGEMENT, L.P.
.................................................................................

2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         Delaware
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         PN



                                  SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 7 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).


         SAB CAPITAL MANAGEMENT, L.L.C.
.................................................................................

2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         Delaware
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         OO



                                  SCHEDULE 13G

CUSIP No.: 02503X105                                          Page 8 of 14 Pages

.................................................................................

1.       Names of Reporting Persons.

         I.R.S. Identification Nos. of above persons (entities only).


         SCOTT A. BOMMER
.................................................................................
2.       Check the Appropriate Box if a Member of a Group

         (a) [X]

         (b) [ ]
.................................................................................

3.       SEC Use Only
.................................................................................

4.       Citizenship or Place of Organization

         United States of America
.................................................................................

Number of       5.     Sole Voting Power                  - 0 -
Shares
Beneficially    ................................................................
Owned by Each
Reporting       6.     Shared Voting Power                - 0 -
Person With     ................................................................

                7.     Sole Dispositive Power             - 0 -
                ................................................................

                8.     Shared Dispositive Power           - 0 -
.................................................................................

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         - 0 -
.................................................................................

10.      Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
         Instructions)

         | |
.................................................................................

11.      Percent of Class Represented by Amount in Row (9)

         0%
.................................................................................

12.      Type of Reporting Person:

         IN



                                                              Page 9 of 14 Pages

Item 1(a).        Name of Issuer:

                  American Capital Agency Corp. (the "Issuer").

Item 1(b).        Address of Issuer's Principal Executive Offices:

                  2 Bethesda Metro Center, 14th Floor, Bethesda, Maryland 20814

Item 2(a).        Name of Person Filing:

                  This  Statement  is filed on behalf  of each of the  following
persons (collectively, the "Reporting Persons"):

                  i)   SAB Capital Partners, L.P. ("SAB");

                  ii)  SAB  Capital  Partners  II,  L.P. ("SAB II", and together
with SAB, the "Domestic Partnerships");

                  iii) SAB Overseas Master Fund, L.P. (the "Master Fund");

                  iv)  SAB Capital Advisors, L.L.C. (the "General Partner");

                  v)   SAB Capital Management, L.P. (the "Investment Manager");

                  vi)  SAB Capital Management, L.L.C. (the "IMGP"); and

                  vii) Scott A. Bommer ("Mr. Bommer").

                  This Statement  relates to Shares (as defined herein) held for
the accounts of each of SAB, SAB II, and the Master  Fund.  The General  Partner
serves as the  general  partner  of each of the  Domestic  Partnerships  and the
Master Fund. The Investment  Manager serves as the investment manager of each of
the Domestic  Partnerships  and the Master Fund.  The IMGP serves as the general
partner of the Investment  Manager.  Mr. Bommer serves as the managing member of
each of the General Partner and the IMGP.

                  Any disclosures  herein with respect to persons other than the
Reporting Persons are made on information and belief after making inquiry to the
appropriate party.

Item 2(b).        Address of Principal Business Office or, if None, Residence:

                  The address of the  principal  business  office of each of the
Reporting Persons is 767 Fifth Avenue, 21st Floor, New York, New York 10153.

Item 2(c).        Citizenship:

                  i)   SAB is a Delaware limited partnership;

                  ii)  SAB II is a Delaware limited partnership;



                                                             Page 10 of 14 Pages

                  iii) The  Master Fund is a  Cayman  Islands  exempted  limited
partnership;

                  iv)  The General  Partner  is a  Delaware  limited   liability
company;

                  v)   The Investment Manager is a Delaware limited partnership;

                  vi)  The IMGP is a Delaware limited liability company; and

                  vii) Mr. Bommer is a citizen of the United States of America.

Item 2(d).        Title of Class of Securities:

                  Common Stock, par value $0.01 (the "Shares")

Item 2(e).        CUSIP Number:

                  02503X105

Item 3.           If This Statement is Filed  Pursuant  to ss.ss.240.13d-1(b) or
                  240.13d-2(b) or (c), Check Whether the Person Filing is a:

                  This Item 3 is not applicable.

Item 4.           Ownership:

Item 4(a).        Amount Beneficially Owned

                  As  of December 31, 2008, none  of the  Reporting  Persons may
be deemed to  beneficially own any Shares.

Item 4(b).        Percent of Class:

                  The  number of Shares of which the  Reporting  Persons  may be
deemed to be the  beneficial  owner of  constitutes  0% of the  total  number of
Shares outstanding.




                                                             Page 11 of 14 Pages


Item 4(c).        Number of Shares of which such person has:

SAB:
- ----

(i) Sole power to vote or direct the vote:                                     0

(ii) Shared power to vote or direct the vote:                                  0

(iii) Sole power to dispose or direct the disposition of:                      0

(iv) Shared power to dispose or direct the disposition of:                     0


SAB II:
- -------

(i) Sole power to vote or direct the vote:                                     0

(ii) Shared power to vote or direct the vote:                                  0

(iii) Sole power to dispose or direct the disposition of:                      0

(iv) Shared power to dispose or direct the disposition of:                     0


The Master Fund:
- ----------------

(i) Sole power to vote or direct the vote:                                     0

(ii) Shared power to vote or direct the vote:                                  0

(iii) Sole power to dispose or direct the disposition of:                      0

(iv) Shared power to dispose or direct the disposition of:                     0


The General Partner, Investment Manager, the IMGP and Mr. Bommer:
- -----------------------------------------------------------------

(i) Sole power to vote or direct the vote:                                     0

(ii) Shared power to vote or direct the vote:                                  0

(iii) Sole power to dispose or direct the disposition of:                      0

(iv) Shared power to dispose or direct the disposition of:                     0


Item 5.           Ownership of Five Percent or Less of a Class:

                  If this statement is being filed to report the fact that as of
the date hereof the reporting  person has ceased to be the  beneficial  owner of
more than five percent of the class of securities, check the following |X|.




                                                             Page 12 of 14 Pages

Item 6.           Ownership of More than Five Percent on Behalf of Another
                  Person:

                  This Item 6 is not applicable.

Item 7.           Identification  and  Classification  of  the  Subsidiary Which
                  Acquired  the Security Being Reported on By the Parent Holding
                  Company:

                  This Item 7 is not applicable.

Item 8.           Identification and Classification of Members of the Group:

                  See disclosure in Item 2 hereof.

Item 9.           Notice of Dissolution of Group:

                  This Item 9 is not applicable.

Item 10.          Certification:

                  By signing below each of the Reporting Persons certifies that,
to the best of their knowledge and belief, the securities referred to above were
not  acquired and are not held for the purpose of or with the effect of changing
or influencing the control of the issuer of the securities and were not acquired
and are not  held in  connection  with or as a  participant  in any  transaction
having that purpose or effect.





                                                             Page 13 of 14 Pages


                                    SIGNATURE

         After reasonable  inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.

Date: February 17, 2009

                          /s/ Brian Jackelow
                          -----------------------------------------------------
                          Brian Jackelow, attorney-in-fact for Scott A. Bommer,
                          individually and (a) as managing member of SAB Capital
                          Advisors, L.L.C., for itself and as the general
                          partner of (i) SAB Capital Partners, L.P.; and (ii)
                          SAB Capital Partners II, L.P.; and (iii) SAB Overseas
                          Master Fund, L.P.; and (b) as managing member of SAB
                          Capital Management, L.L.C., for itself and as the
                          general partner of SAB Capital Management, L.P.





                                                             Page 14 of 14 Pages


                                    EXHIBIT 1

                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE  PRESENT,  that I, Scott A. Bommer,  hereby make,
constitute and appoint each of Michael  Casey,  Brian Jackelow and Alessandro De
Giorgis,  acting individually,  as my agent and attorney-in-fact for the purpose
of  executing in my name,  (a) in my personal  capacity or (b) in my capacity as
managing member of or in other capacities with SAB Capital  Advisors,  L.L.C., a
Delaware  limited  liability  company,  and each of its  affiliates  or entities
advised or  controlled by me or SAB Capital  Advisors,  L.L.C.,  all  documents,
certificates,  instruments,  statements, filings and agreements ("documents") to
be filed with or delivered to any foreign or domestic governmental or regulatory
body or  required or  requested  by any other  person or entity  pursuant to any
legal  or  regulatory  requirement  relating  to  the  acquisition,   ownership,
management or disposition of securities, futures contracts or other investments,
and any other  documents  relating  or  ancillary  thereto,  including,  without
limitation,  all documents relating to filings with the United States Securities
and Exchange  Commission  (the "SEC") pursuant to the Securities Act of 1933, as
amended, or the Securities Exchange Act of 1934, as amended (the "Act"), and the
rules and regulations promulgated thereunder, including, without limitation: (1)
all documents relating to the beneficial  ownership of securities required to be
filed  with the SEC  pursuant  to  Section  13(d) or  Section  16(a) of the Act,
including, without limitation: (a) any acquisition statements on Schedule 13D or
Schedule  13G and  any  amendments  thereto,  (b) any  joint  filing  agreements
pursuant to Rule 13d-1(k),  and (c) any initial  statements of, or statements of
changes in,  beneficial  ownership of securities on Form 3, Form 4 or Form 5 and
(2) any  information  statements  on Form 13F  required to be filed with the SEC
pursuant to Section 13(f) of the Act.

         All  past  acts  of  these  attorneys-in-fact  in  furtherance  of  the
foregoing are hereby ratified and confirmed.

         This  Power of  Attorney  shall  remain in  effect  until  revoked,  in
writing, by the undersigned.

         IN  WITNESS  WHEREOF,  the  undersigned  has  executed  this  Power  of
Attorney, this 9th day of August 2006.


                                  /s/ Scott A. Bommer
                                  -------------------------
                                  Scott A. Bommer