-- A key Senate leader is urging General Motors Co. and Chrysler Group LLC to negotiate a compromise with groups representing more than 2,000 dealerships that are slated to close as the automakers restructure.

Sen. Richard Durbin of Illinois, the No. 2 Democrat in the Senate, on Monday sent letters to GM President and CEO Fritz Henderson and Chrysler CEO Sergio Marchionne urging them to reach a deal on the dealership issue "at the negotiating table."

The House passed a spending bill in July that seeks to reverse Chrysler's closing of 789 dealers and GM's planned closing of at least 1,300 dealerships by October 2010. A separate House bill has 272 supporters.

A Senate version now has 37 supporters, though neither Michigan senator supports the bill.

"While I have not foreclosed the option of supporting a legislative solution to address these concerns, I believe very strongly that these issues can and should be resolved outside the legislative process," Durbin wrote.

GM spokesman Greg Martin said the company hopes to "achieve an amicable, non-legislative solution" to dealers' concerns.

Chrysler has been in contact with Durbin's office and is "open to discussion on all of the relevant issues," a representative said.

Separately, the Transportation Department has approved $2.38 billion in payments to auto dealers for 565,690 vehicles sold under the $3 billion "cash for clunkers" program . It is reviewing another 55,000 applications.

The agency has paid 478,000 vouchers for about 70 percent of the funds sought. It has rejected nearly one in 10 applications, while dealers withdrew 9,000 applications. In total, the department has rejected 60,043 applications seeking $251 million. Another 55,423 applications seeking $232 million are under review.

In total, dealers sought $2.868 billion and have been approved for 83 percent of the money requested.

The Transportation Department figures mean that as much as $300 million could be left in the $3 billion program.

Transportation Secretary Ray LaHood did not categorically rule out reopening the program. "The program under the law goes until November," he told reporters.