WASHINGTON (Reuters) - A member of the U.S. Senate Democratic leadership said on Wednesday that there was broad bipartisan support for financial rescue proposals the Senate will vote on tonight and predicted they will be approved.

Democratic Sen. Charles Schumer of New York said feedback from constituents show Americans' views on the package have changed since the House of Representatives rejected the bill on Monday.

"The tone has changed," Schumer said on CNBC television. "Last week, it was overwhelmingly vote 'no', now it is 'well you may not like this plan, but do something."

While he said that some idea about changing so-called mark-to-market rules for banks' accounting of their assets may need revision, they will not be part of the bill the Senate votes on Wednesday.

"To do it quickly would be a mistake," Schumer said in response to a question. "That's the kind of thing that has to be left for broad regulatory reform" next year.

A Senate vote was expected sometime in the early evening after a debate that could last some time.

"On the Senate side, it seems there is broad bipartisan support," Schumer said, especially since additions were made to the proposals the House rejected, such as increasing federal insurance on bank deposits and extending some tax breaks for business.

"So, it's a better package and if I had to guess I'd think it'll pass both bodies," said Schumer, adding: "Obviously it's a tougher road in the House."

There was no word yet on Wednesday about how soon another House vote might be scheduled, but the White House was pressing for one this week.

"We're seeing increased evidence of the credit squeeze on small businesses and municipalities all across the country, so it's critically important that we approve legislation this week and limit further damage to our economy," White House spokesman Tony Fratto said on Wednesday morning.

Once it passes both the House and Senate, the financial rescue package would go to President George W. Bush and be signed into law.

That would enable the Treasury department to begin buying up to $700 billion of illiquid and unwanted securities from banks in the hope that will unclog credit markets and persuade banks to resume normal lending, Schumer said.

Many details of how the bad assets would be purchased remain to be worked out but Schumer said that expected auctions or other means for taking the assets off banks' hands would happen "rather quickly."

(Reporting by Glenn Somerville; Editing by Chizu Nomiyama)