The "cash for clunkers" program is an example of the Obama administration's mismanagement of the economy, Senate Minority Leader Mitch McConnellMitch McConnellLawmakers push one-week stopgap funding bill Overnight Finance: Inside Trump's tax plan | White House mulls order pulling out of NAFTA | New fight over Dodd-Frank begins Dem rep: Trump's tax plan as believable as 'magic, unicorns or Batman' MORE (R-Ky.) asserted Monday.

McConnell, an original opponent of the auto rebate program, took to the Senate floor this afternoon to criticize the plan ahead of a vote expected this week in his chamber to offer a $2 billion extension to the initiative.

"Last week we saw the administration's tendency to miss the mark on economic estimates again with the so-called 'cash for clunkers' program," McConnell said in prepared remarks. "We were told this program would last for several months. As it turned out, it ran out of money in a week, prompting the House to rush a $2 billion dollar extension before anybody even had time to figure out what happened with the first billion."

While the extended funding for the program passed the House fairly easily, some senators in both parties have expressed a reluctance to quickly sign off on a bill expected to hit the floor this week.

Transportation Secretary Ray LaHood warned Sunday that the program would have to be suspended next week if the Senate fails to approve more funding this week.

"Americans are telling us that health care is too important to rush," McConnell said. "They're saying it's too important to base our decisions on this issue solely on the estimates that we're getting from the same people who brought us the stimulus and cash for clunkers."