Rescuing Mortgage Giants Could Cost $25B

WASHINGTON — Congress' top budget analyst says a federal rescue of troubled mortgage giants Fannie Mae and Freddie Mac could cost taxpayers as much as $25 billion.

But the director of the Congressional Budget Office, Peter R. Orszag, predicted in a letter to lawmakers today that there's a better than 50% chance the government will not have to step in to prop up the companies by lending them money or buying stock.

Congress is expected to vote this week on a housing measure that includes Treasury Department authority to throw Fannie and Freddie a temporary lifeline.

Treasury Secretary Paulson, who has been pressing for the power, says the backup plan will help calm investors and stabilize financial markets.