The House passed emergency legislation Friday approving an additional $2 billion for the "cash for clunkers" program, whose immediate popularity this week threatened to sink the fledgling program.

A Senate vote is expected next week on the emergency infusion and could come as soon as Monday. The House scrambled to schedule their vote on the final day of their session before a month-long summer recess.

Skipping over regular procedure to obtain an immediate floor vote, House Democrats' presented a bill that would shuffle around funds from the Recovery and Reinvestment Act, an emergency stimulus for the original $1 billion budget for rebates on new cars that lawmakers worried had been exhausted in only a week. The bill passed 316-109.

President Obama said he was "very pleased" that lawmakers had moved quickly to save the program, but Republicans blasted the speed of the vote, accusing Democrats of jamming the legislation through. The bill includes hand-written marks on its margins, a sign of the haste in which the legislation was written.

Click here to see the bill.

"Thanks to quick bipartisan responses, we're doing everything possible to continue this program and to continue helping consumers and the auto industry contribute to our recovery." Obama said Friday.

Democrats have hailed the success of the clunkers program, which has fueled hundreds of thousands of new car sales this week -- a sign that "consumers have spoken with their wallets," said Rep. David Obey, D-Wisc.

But congressional Republicans began mounting a campaign Friday against the "absurdity" of another infusion of money, calling it the second bailout in three days following a $14 billion boost in funds for highways and other projects.

"If there was an 'extra' $2 billion in a stimulus program that was suitable for a different purpose, why did we spend the $2 billion in the first place?" said Rep. Jerry Lee of California, the ranking Republican on the House Appropriations Committee. "How many other billions of dollars are in the stimulus not being spent that we can return to the taxpayers?"

The White House said the program would continue despite mounting concern over funding, which would not be approved before a Senate vote, which was not possible Friday.

"We're working that through," said David Axelrod, a senior adviser to President Obama. "The program is going to continue."

White House spokesman Robert Gibbs said the program remain alive "this weekend" and anyone looking to buy a car through the program should still do so -- but would not commit to any timeframe beyond that.

Republican leadership said that in the face of overwhelming support they would not be able to sink the bill, but that many Republicans would likely end up voting against it. The legislation may face stiffer opposition in the Senate, where Republican leaders expressed their fervent disapproval.

"We're now again bailing out the automobile corporations, two of which we own," said Sen. John McCain, R-Ariz. "It's remarkable."

Republicans in the House and Senate said early handling of the program sent worrying signals that the administration was not prepared to handle legislation on health care reform, which will involve far larger sums of money.

House Minority Leader John Boehner, R-Ohio, said it was unclear how many Republicans would support the infusion plan. "There are a lot of questions about how the administration administered this program. If they can't handle something as simple as this, how would we handle health care?" he said, a sentiment echoed by Sen. David Vitter, R-La.

"Cash for Clunkers has only been active for a short period of time, and it has already run a deficit," Senator Vitter said in a statement. "But we are supposed to trust the president and his Congressional allies to accurately 'reform' the health care industry, which makes up one-seventh of our entire economy?"

Called the Car Allowance Rebate System, or CARS, the program offers owners of old cars and trucks $3,500 or $4,500 toward a new, more fuel-efficient vehicle, in exchange for scrapping their old vehicle. Congress last month approved the plan to boost auto sales and remove some inefficient cars and trucks from the roads.

The program was scheduled to last through Nov. 1 or until the money ran out, but few predicted the fund would run out so quickly. The $1 billion in funding would provide up to 250,000 new car sales.

It was unclear how many cars had been sold under the program. Sen. Debbie Stabenow, D-Mich., said about 40,000 vehicle sales had been completed through the program but dealers estimated they were trying to complete transactions on another 200,000 vehicles, putting the amount of remaining funding in doubt.

John McEleney, chairman of the National Automobile Dealers Association, said many dealers have been confused about whether the program will be extended and for how long. Many had stopped offering the deals Thursday after word came out that the funds available for the refunds had been exhausted.

"We are hoping for some clarity from the White House and Congress before the day is over," McEleney said Friday.

The clunkers program was set up to boost U.S. auto sales and help struggling automakers through the worst sales slump in more than a quarter-century. Sales for the first half of the year were down 35 percent from the same period in 2008, and analysts are predicting only a modest recovery during the second half of the year.

So far this year, sales are running under an annual rate of 10 million light vehicles, but as recently as 2007, automakers sold more than 16 million cars and light trucks in the United States.

Earl Stewart, who owns a Toyota dealership in North Palm Beach, Fla., said the changing messages on the program has created confusion among his customers and his staff. Stewart's accounting department also could only enter about a dozen of the 47 sales he made into the government Web site set up to handle the transactions, leaving him wondering if he will get refunded for the remaining vouchers.

With so much uncertainty surrounding the program, Stewart said he planned to continue to sell cars under the program Friday but would delay delivering the new vehicles and scrapping the trade-ins. Drivers would be put in loaners until he was absolutely certain the program was still going.

"It's been a total panic with my customers and my sales staff. We are running in one direction and then we are running in another direction," he said.

FOX News' Chad Pergram contributed to this report.