Bankruptcy once again is a plausible option for one or more of Detroit's Big Three automakers as a financial rescue is at risk of stalling in Congress.

General Motors Corp., Ford Motor Co. and Chrysler LLC are all lobbying for $25 billion in emergency loans in exchange for a government ownership stake in the car companies. Democrats also support a plan that would allow the auto industry access to the $700 billion Wall Street rescue money.

Opposition from Republican lawmakers and the Bush administration could threaten the plan. Debate in the Senate is scheduled to begin Monday, with a test vote expected two days later.

House GOP leader John Boehner of Ohio issued a statement Thursday promising to oppose any new auto industry loans.

"Spending billions of additional federal tax dollars with no promises to reform the root causes crippling automakers' competitiveness around the world is neither fair to taxpayers nor sound fiscal policy," Mr. Boehner said.

Treasury Secretary Henry Paulson said Wednesday the auto sector was "critical" but that the financial industry rescue was not designed for car companies.

Congress may wait until President-elect Barack Obama is sworn in Jan. 20 to provide further help to the carmakers.

"I think all three domestic companies are counting pretty heavily on some kind of aid from the federal government," said Jack Nerad, editorial director of Kelley Blue Book.

General Motors chairman Rick Wagoner has said bankruptcy is not an option the company is considering.

GM already has announced a delay in product research and development for the next two years -- a step that most analysts say will put the company at a severe marketing disadvantage. It also has reduced benefits and announced plans to eliminate 3,600 jobs and slash production at nine plants.

Chrysler, owned by Cerebrus LLD, is now a private entity that keeps financial information close to the vest, but the company's situation is so dire that it was involved in acquisition talks with GM. Those talks have ended, at least temporarily.

Although Ford is thought to be somewhat better off, it still has chronic financial problems. Company officials said Ford has burned through $7.7 billion in cash and the company posted an operating loss of $2.98 billion for the third quarter.

Ford plans to cut 2,260 jobs and merit pay for salaried employees.

Given their financial difficulties, bankruptcy looms as a real option, although it is one that analysts warn would have an impact on the economy.

"You would lose major, major amounts of employment. And you are looking at the fact that a lot of people have stock ownership in domestic car companies," Mr. Nerad said. "There would be reverberations through industries elsewhere. You probably would also trigger other bankruptcies."

A number of foreign car makers, notably Honda and Toyota, which have major plants in the United States, could be imperiled because suppliers that would go out of business because of a Big Three bankruptcy also provide parts and supplies for the Japanese firms.

GM and Ford also have substantial numbers of plants and employees all over the world. If the firms go out of business, the economic impact would worsen the global recession.

Some analysts believe declaring bankruptcy might speed a rebirth of the three companies.

"It's time to take GM, Ford, and Chrysler through the purgatory of Chapter 11, where they can work off their sins, jettison and restructure bond obligations into common shares and finally relieve themselves of the yoke of the UAW contract," said Peter Morici, a University of Maryland business professor who tracks the auto industry.

"If one or more of the Big Three declare bankruptcy," Dr. Morici said, "they would get bankruptcy financing. They would pay their suppliers and pay wages to their current workers.

"But it would mean the current UAW contract would go out the window. Then they would negotiate concessions on a new contract, or they would close."