WASHINGTON — Governors and business lobbyists pressured lawmakers Wednesday to pass a $700 billion financial industry bailout as top lawmakers prepared for another face-off on the issue — this time in the Senate.

"There is a time for partisanship and there is a time for getting things done," Texas Gov. Rick Perry and West Virginia Gov. Joe Manchin wrote in a letter to members of Congress.

"Americans across the country and in every demographic are feeling the pinch. If Congress does not act soon, the situation will grow appreciably worse. It's time for leadership. Congress needs to act now," they wrote.

Perry heads the Republican Governors Association while Manchin leads the Democratic governors group. Their letter was aimed at signaling there are home-state political reasons for approving the massive bailout, in which the government would spend billions of dollars to buy risky mortgage securities that are choking the financial system.

Adding its voice, the U.S. Chamber of Commerce launched 30-second radio ads in the Washington area aimed directly at lawmakers.

"Inaction, without a doubt, would cause our economy to collapse," R. Bruce Josten, the chamber's executive vice president, says in the ad. "Congress, do not delay."

The new lobbying initiative came as the Senate prepared for an evening vote on a version of the bill overhauled to attract additional support. Changes include an increase in the size of bank deposits insured by the Federal Deposit Insurance Corp., from $100,000 to $250,000.

Congressional leaders said those additions, plus complaints from constituents furious over Monday's stock market plunge, have improved the prospects for the measure's approval. After the Senate's expected passage, a House vote could come later this week.

In a letter to members of Congress Tuesday, more than 50 business trade groups said legislators had to quickly act "to prevent a meltdown" of the country's capital markets and disappearance of credit, making loans for businesses and individuals harder to come by.

Groups signing the letter included the National Association of Manufacturers, the American Banking Association and the National Association of Realtors.

The White House also stepped in by urging outside groups to press lawmakers to vote "yes" when Congress takes up the rescue legislation anew, according to a senior administration official who spoke on condition of anonymity to discuss internal strategy.

President Bush has made a nationally televised speech and met with congressional leaders and the two main presidential candidates at the White House in a futile effort to round up votes for the legislation.

Monday's House rejection of the package has left business groups fuming.

Scott Talbott, senior vice president of government affairs at the Financial Services Roundtable, complained that lawmakers are hearing two different arguments.

"In one they have constituents asking: 'Why are we helping industry with this self-inflicted wound? This bill doesn't affect me,"' said Talbott, whose group represents 100 of the country's largest financial services companies. "In the other ear, they were hearing doom and gloom" from the administration and Federal Reserve Chairman Ben Bernanke, said Talbott.

The U.S. Chamber of Commerce said its annual tally of how individual lawmakers vote on business issues would include the votes on the rescue plan — in effect daring lawmakers to oppose the legislation.

Such warnings, though, fell short Monday against complaints from angry constituents. Public reaction to the House vote — and the Dow Jones industrial average's 778-point plunge — could again carry the day when lawmakers revisit the legislation.

"I'm sure the lobbyists are trying, but I don't think even an army of lobbyists can overcome the public response, which is huge," said Rep. John Campbell, R-Calif., who cast a "yes" vote.

Campbell said while calls to his office against the bill outnumbered those in favor by 8-to-1, most constituents voiced support for the measure on Tuesday.

"The calls now are saying, 'I lost 10 percent of my retirement yesterday,"' Campbell said. "The calls I'm getting are thanking me now."

Aides to lawmakers who opposed the legislation said that while the number of constituents calling or e-mailing on Tuesday who supported the bill increased, majorities were still against the bailout.

The Center for Responsive Politics, a private group that tracks money in politics, noted that House members who supported the bailout have received 51 percent more in campaign contributions from the finance, insurance and real estate sectors than those who opposed the legislation.