WASHINGTON – The U.S. Senate approved and sent to the White House on Thursday a $2 billion extension of the cash for clunkers autos sales incentive program.

The measure, approved by 60 to 37, extends the surprisingly successful program that has raised sales of the U.S. auto industry.

The initial $1 billion of funding approved in June for clunker business has generated more than $920 million in rebates and more than 220,000 in auto sales.

Supported by the incentive program, U.S. auto sales overall were down about 12 percent in July from a year earlier, but it was their best performance this year.

The program offers consumers a federally backed rebate of up to $4,500 if they trade in old vehicles for new, more fuel efficient ones.

The House of Representatives approved the extension on July 31, and President Barack Obama is expected to quickly sign it.

Supporters of the extension defeated several Republican amendments aimed at derailing the plan in the Senate.

(Reporting by John Crawley; Editing by Toni Reinhold)