And Democratic Rep. Shelley Berkley of Nevada said she would back the bill after business leaders in her Las Vegas-area district made it clear how much it was needed. She said, "There isn't a segment of the population that hasn't been slammed and is not asking for some relief."

Emboldened by the feverish bidding for votes, other members of both parties were demanding substantial changes to the legislation before they would vote for it. A group of Republican opponents indicated they'd back it if the price tag were slashed to $250 billion and several special tax breaks added by the Senate — including for children's archery bow makers, imported rum producers and racetrack owners — were removed. Democrats wanted to add a way to pay for the bailout and more help for homeowners staring at foreclosure.

Speaker Nancy Pelosi, D-Calif., said no such revisions were possible because they would slow the measure's enactment and further shake markets.

"I don't think that any changes here will do what we need to do, which is right now to send a message of confidence to the markets that Congress will act," she said.

The Senate breathed new life into the measure Wednesday after the stinging House defeat, voting 74-25 to approve the bailout, with additions designed to appeal to key constituencies. Business lobbyists were also inundating Capitol Hill in a rush to win over wavering lawmakers in both parties.

The changes helped satisfy some Republican critics, but angered conservative "Blue Dog" Democrats — of whom Matheson is a member — who are concerned about swelling the deficit. Still, Hoyer predicted the number of Democratic defectors "is going to be minimal."

A handful of Republicans who voted for the measure Monday appeared to be backing away from it.

"We can save ourselves from this rush to judgment," said Rep. Spencer Bachus of Alabama, the top Republican on the Financial Services Committee. He argued Congress should approve just a fraction of the money requested and then "go home and answer the wrath of our constituents."

In efforts to appease GOP opponents, the Senate added a provision to raise, from $100,000 to $250,000, the limit on federal deposit insurance.

House Republicans were also cheered by a decision by the Securities and Exchange Commission this week to ease rules that force companies to devalue assets on their balance sheets to reflect the price they can get on the market.

The developments on Wednesday prompted one Republican, Rep. John Shadegg of Arizona, to say he would support the new bill.