Legislation that would add $2 billion to a cash-for-clunkers program aimed at spurring U.S. automobile sales could move quickly through the U.S. Congress, Michigan Senator Debbie Stabenow said on Friday.

Speaking to reporters, Stabenow and fellow Democrat Carl Levin said a vote could come as early as Friday in the House of Representatives to extend the popular program that was recently enacted. The House is scheduled to recess later in the day for its annual August vacation.

The government's $1 billion cash-for-clunkers program ran out of money after an unexpected avalanche of business exhausted its funds, the Obama administration said late Thursday. The program was part of a congressional effort to help domestic automakers, especially General Motors Corp and Chrysler, which briefly went bankrupt earlier this year.

Stabenow added that she was in talks with Senate Democratic leaders to move the extension quickly through the Senate, but did not yet know when that might happen.

The White House supports and helped draft the legislation, which would use money from an energy loan guarantee program included in the economic stimulus package enacted in February, Stabenow and Levin said.

President Barack Obama's economic team, along with officials from the Transportation Department and Office of Management and Budget, were working with Congress to find more money for the clunkers program, a White House spokesman said.

A House Democratic aide, who asked not to be identified, said leaders were trying to get an agreement with Republicans to bring the measure onto the House floor on Friday. While the bill as introduced would provide $2 billion, that amount could change, the aide said without providing specifics.

Stabenow cautioned that some Republicans were likely to oppose additional money for the popular cash-for-clunkers program.

Rep. Jeb Hensarling, a senior Republican on the House Financial Services Committee, issued a statement criticizing the cash-for-clunkers program as an example of the government picking winners and losers in an economic crisis that affected a broad number of industries and markets.

(Reporting by Richard Cowan, Writing by Julie Vorman, Editing by Phil Berlowitz)