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Exhibit 10.1

AMENDMENT ONE TO REVOLVING CREDIT AGREEMENT

        THIS AMENDMENT ONE TO REVOLVING CREDIT AGREEMENT (this "Amendment")
dated as of August 30, 2005, by and between EDISON MISSION MARKETING &
TRADING, INC., a California corporation, as borrower ("Borrower"), and MIDWEST
GENERATION, LLC, a Delaware limited liability company, as lender ("Lender").

        WHEREAS, the Borrower and the Lender entered into a Revolving Credit
Agreement dated as of April 27, 2004 (the "Credit Agreement");

        WHEREAS, the Borrower has requested that the Lenders increase the amount
of loans permitted to be made under the Credit Agreement; and

        WHEREAS, Lender is willing to agree to the amendments provided for in
this Amendment on the terms and conditions hereof.

        ACCORDINGLY, the parties hereto agree as follows:

        Section 1.    Definitions.    Except as otherwise defined in this
Amendment, terms defined in the Credit Agreement are used herein (and in the
introductions and recitals hereto) as defined therein.

        Section 2.    Amendment to the Credit Agreement.    The Credit Agreement
shall hereby be amended as follows:

        (a)   Section 2.1 of the Credit Agreement is hereby amended and restated
in its entirety as follows:

Borrowings/Letters of Credit. From time to time on any day occurring prior to
the Termination Date, Lender shall make loans to Borrower (each a "Revolving
Loan"), and/or cause to be issued letters of credit on behalf of Borrower (each
a "Letter of Credit") in the amounts requested in writing by a Borrower's
Representative; provided that (i) the aggregate amount of Revolving Loans and
Letters of Credit outstanding shall not at any time exceed $500,000,000 (the
"Revolver Commitment") and (ii) Lender shall not be required to make any such
loan or cause the issuance of such letters of credit unless doing so would
constitute the provision of Permitted Marketing Support by Lender.    Borrower
may from time to time borrow, prepay, in whole or in part, and reborrow
Revolving Loans and/or request the cancellation or reissuance of Letters of
Credit. Simultaneously herewith, borrower shall execute a promissory note for
Revolving Loans in form and substance substantially similar to Exhibit A hereto
or otherwise in form and substance as is agreed by the parties hereto (the
"Revolver Note"), in either case in the principal amount of the Revolver
Commitment.

        (b)   The form of Note attached as Exhibit A to the Credit Agreement is
hereby amended and restated in its entirety as set forth in Exhibit A to this
Amendment. Borrower shall execute and deliver to Lender a new promissory note in
the form of Exhibit A to this Amendment (the "Replacement Note"), whereupon
Lender shall (a) update the grid of the Replacement Note to reflect all
Borrowings then in place under the Credit Agreement; and (b) cancel and return
to Borrower the Note previously executed in connection with the Credit
Agreement.

        Section 3.    Miscellaneous.    Except as expressly amended hereby, all
of the terms and provisions of the Credit Agreement are and shall remain
unchanged and in full force and effect. This Amendment may be executed in any
number of counterparts, all of which taken together shall constitute one and the
same instrument and any of the parties hereto may execute this Amendment by
signing any such counterpart. This Amendment shall be governed by, and construed
in accordance with, the law of the State of New York.

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        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered by their respective officers thereunto duly
authorized as of the day and year first above written.

    EDISON MISSION MARKETING & TRADING, INC.
 
 
By:
 
/s/ Paul Jacob

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Name: Paul Jacob
Title: President
 
 
MIDWEST GENERATION, LLC,
 
 
By:
 
/s/ Jim Scilacci

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Name: Jim Scilacci
Title: Senior Vice President and Chief Financial Officer

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EXHIBIT A
to Credit Agreement

[FORM OF]
NOTE

$500,000,000   [DATE]

        FOR VALUE RECEIVED, the undersigned, EDISON MISSION MARKETING
TRADING, INC., a California corporation ("Borrower"), promises to pay to the
order of MIDWEST GENERATION, LLC, a Delaware limited liability company
("Lender"), on or before the Termination Date, the principal sum of $500,000,000
or such lesser amount which Lender advances to Borrower from time to time
pursuant to that certain Revolving Credit Agreement, dated as of April 27, 2004,
as amended from time to time (the "Revolving Credit Agreement"), by and between
Borrower and Lender. All requests by Borrower for advances under this Note shall
be made in such manner and form and with such prior notice as prescribed in the
Revolving Credit Agreement. Capitalized terms used but not defined herein shall
have the meanings given to such terms in the Revolving Credit Agreement.

        Borrower also promises to pay to Lender the amounts specified in
Section 2.4 of the Revolving Credit Agreement. Payments of such amounts and of
principal are to be in Dollars in same day or immediately available funds to the
account designated in a writing delivered by Lender to Borrower.

        This Note evidences Indebtedness incurred under the Revolving Credit
Agreement to which reference is made for a statement of the terms and conditions
on which Borrower is permitted and required to make prepayments and repayments
of principal of the Indebtedness evidenced by this Note and on which such
Indebtedness may be declared to be immediately due and payable.

        The Borrower hereby irrevocably authorizes the Lender to make (or cause
to be made) appropriate notations on the grid attached to this Note (or on any
continuation of such grid), which notations, if made, shall evidence, inter
alia, the date of, the outstanding principal balance of the Revolving Loans
evidenced hereby. Such notations shall be rebuttable presumptive evidence of the
information so set forth; provided, however, that the failure of Lender to make
any such notations shall not limit or otherwise affect any obligations of
Borrower.

        All parties hereto, whether as makers, endorsers or otherwise, severally
waive presentment for payment, demand, protest and notice of dishonor.

        If any payment on this Note becomes due and payable on a date which is
not a Business Day, such payment shall be made on the next succeeding Business
Day.

        THIS NOTE HAS BEEN DELIVERED IN NEW YORK AND SHALL BE DEEMED TO BE A
CONTRACT MADE UNDER AND GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW YORK.

    EDISON MISSION MARKETING & TRADING, INC.
 
 
By:
 
    

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Name:
Title:

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REVOLVING LOANS AND PRINCIPAL PAYMENTS

Date

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  Amount of
Revolving Loan

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  Amount of
Principal Repaid

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  Unpaid Principal
Balance

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  Notation Made By

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Exhibit 10.1

AMENDMENT ONE TO REVOLVING CREDIT AGREEMENT

EXHIBIT A to Credit Agreement

[FORM OF] NOTE
REVOLVING LOANS AND PRINCIPAL PAYMENTS