Washington, D.C. ? Congress approved a “cash for clunkers” program Thursday to provide government incentives of $3,500 to $4,500 to motorists who trade in their gas guzzlers for more fuel efficient vehicles after Senate Democrats narrowly defeated a Republican effort to kill the plan.

Auto state senators said the program would help hard-pressed car dealers and automakers by bringing buyers into showrooms, and they got help from President Barack Obama and Vice President Joe Biden, who made calls to wavering Democrats urging them to keep the plan alive.

“This is an emergency for families and small businesses — for an industry that has been the backbone of our economy for a generation,” said Sen. Debbie Stabenow, D-Mich., who sponsored the proposal.

Opponents said it would increase the federal debt without doing much to get expensive-to-operate vehicles off the roads.