WASHINGTON – More than two years into the nation's housing downturn, Congress put a massive mortgage rescue and reform bill on a fast track toward enactment Wednesday.

With President Bush conceding that the measure was too important to veto, the American Housing Rescue and Foreclosure Prevention Act won House approval on a 272-152 vote. The Senate is expected to approve it as early as Friday, despite conservatives' continuing objections.

The bill would provide help to millions of borrowers, lenders and others coping with the worst housing market since the Great Depression.

But taxpayers could feel the bite: The rescue plan has an outside chance of costing more than $100 billion, depending on whether the reforms help the housing market "turn the corner" as Treasury Secretary Henry Paulson predicted Wednesday.

The package includes help for many:

•Homeowners sliding toward foreclosure will find it easier to refinance their loans.

•Regulators will get tougher rules to end bad lending practices.

•Troubled mortgage finance giants Fannie Mae and Freddie Mac will get new federal lifelines.

•First-time homebuyers will get tax breaks. Local governments will get funds to clean up neighborhoods devastated by foreclosures.

"This is a balanced bill," House Financial Services Committee Chairman Barney Frank, D-Mass., said on the House floor. Mr. Frank, the legislation's chief architect, has been putting the bill together for more than a year, struggling all the while to get Mr. Bush and congressional Republicans on board.

House Majority Leader Steny Hoyer, D-Md., said the legislation would help end "the vicious cycle of foreclosures" by allowing at least 400,000 struggling borrowers to refinance their mortgages to avoid default. That would help prevent any worsening of "the mortgage crisis that is rocking our economy," he said.

The vote among North Texas lawmakers broke along party lines. The region's eight Republicans all voted against the bill, including Reps. Jeb Hensarling and Pete Sessions of Dallas. The delegation's lone Democrat, Rep. Eddie Bernice Johnson of Dallas, voted for it.

Mr. Sessions said the bill risks a taxpayer bailout by permitting the Treasury Department to inject billions of dollars into Fannie Mae and Freddie Mac – the Federal National Mortgage Association and the Federal Home Mortgage Corp. – should the mortgage giants near failure. At the same time, the legislation creates a new affordable housing fund that is funded by revenues from the two government-sponsored firms.

"We are saying on one hand to Freddie and Fannie: 'We are going to help you, and on the other hand, we are going to hurt you,' " Mr. Sessions said.

On Tuesday, the nonpartisan Congressional Budget Office said the provision that would give the Treasury Department the temporary authority to increase its line of credit to Freddie and Fannie probably would not be used. But it said if Treasury did have to act, the cost probably would amount to $25 billion, and that there was a slight chance it could exceed $100 billion.

The White House said that while it has some objections, most provisions "are too important to the stability of our nation's housing market, financial system, and the broader economy not to be enacted immediately."

The legislation offsets its costs with revenue increases.

The Freddie and Fannie provisions are a major reason that many Republicans remain unhappy about the bill. House Minority Leader John Boehner, R-Ohio, said he was "deeply disappointed" with the Bush administration. On the House floor, he said the bill's passage would amount to "placing taxpayers on the hook for billions and billions of dollars."

Senate Banking Committee Chairman Chris Dodd, D-Conn., and the committee's senior Republican, Richard Shelby of Alabama, gave their blessing to the final House version, saying they wouldn't try to amend it.

But some Senate conservatives say they will keep trying to thwart it. Another provision that particularly rankles them would provide more than $3.9 billion in grants to states and local entities for the purchase and rehabilitation of foreclosed homes.

Fiscal conservatives say taxpayers should not be spending money that would benefit the lenders who own the empty houses. But supporters say entire neighborhoods are being pulled down by dilapidated vacant properties. Cleaning up blight would stabilize prices for everyone, they argue.

Cox News Service and staff writer Dave Michaels contributed to this report.

PROVIDES MORTGAGE REFINANCING ASSISTANCE for at least 400,000 families in their primary residences. To participate, lenders and mortgage investors must take significant losses by reducing the loan principal.

CREATES AN INDEPENDENT REGULATOR to oversee mortgage giants Fannie Mae and Freddie Mac. Increases the limits on loans they can buy or guarantee from $417,000 to $625,500. Creates a trust fund financed by Fannie and Freddie for low-income rental housing.

GIVES THE TREASURY DEPARTMENT temporary authority to increase its line of credit to Freddie and Fannie and buy their stock.

PROVIDES ALMOST $4 BILLION for hard-hit communities to buy and rehabilitate foreclosed homes.

EXPANDS ACCESS FOR FAMILIES to Federal Housing Administration mortgages and for seniors to FHA reverse mortgages.

PROVIDES $15 BILLION in tax benefits, including tax credits to first-time homebuyers, a real property tax deduction for non-itemizers, and an additional $11 billion in mortgage revenue bonds for states.

SOURCES: House Financial Services Committee; Cox News Service