The Republican leader, Senator Mitch McConnell of Kentucky, was noncommittal. The Republicans had a “spirited” discussion about the auto rescue plan, he said, but it was too soon to take a stand because they had just received a final draft of the bill.

“Everybody’s still kind of poring through it, trying to figure out exactly what it does,” Mr. McConnell said. “At this particular juncture, I couldn’t handicap for you the level of support that may exist in our conference. But we did begin a conferencewide learning process during the course of the last hour.”

Even some auto-state lawmakers were unhappy with the bailout plan the White House helped to design. “While I am fighting to save Missouri auto jobs,” said Senator Christopher S. Bond, Republican of Missouri, “Congress is just putting off the inevitable unless we force the companies to reform fundamentally, which this latest plan fails to do and is why I am offering changes to make it work.”

A number of other Senate Republicans said they had every intention of scuttling a taxpayer-financed rescue for General Motors and Chrysler.

Senator Richard C. Shelby of Alabama, the senior Republican on the banking committee, called the proposal “a travesty” and said that he would filibuster the bill. “This is an installment on a huge bailout that will come later,” he said.

Others, while critical of the legislation, suggested there was hope of a compromise.

Senator Bob Corker, Republican of Tennessee, who was working to draft alternative legislation, said the proposal put forward by the White House and Congressional Democrats provided only weak authority for the car czar, who would supervise the sweeping reorganization plans that the automakers have agreed to carry out.