Sen. John ThuneJohn Randolph ThuneHouse, Senate GOP compete for cash Overnight Tech: Alleged robocall kingpin testifies before Congress | What lawmakers learned | Push for new robocall rules | Facebook changes privacy settings ahead of new data law | Time Warner CEO defends AT&T merger at trial Senators grill alleged robocall kingpin MORE (R-S.D.), a potential presidential candidate, this weekend defended his vote for the 2008 Troubled Asset Relief Program (TARP), which Tea Party activists vehemetly oppose.

Thune, who is also a member of the GOP leadership, said that the program deviated from its original intention but said that it was the right vote to make at the time. 

"I have probably been one of the fiercest critics and probably biggest advocates of ending TARP since it was enacted because of how it was used," he said on C-SPAN's Newsmakers program that aired Sunday.

Thune said that he disagreed with the government's decision to buy equity shares in large failed companies, instead of purchasing targeted toxic assets.

"It was wrong philosophically. I hope we get our money back," he said. "How it was used and, in my view, misused is what I've taken issue with."

Thune's vote for TARP, which was widely supported by Democrats and Republicans in the final months of the Bush administration, will likely be a major debate point should he decide to enter the 2012 GOP presidential primary. Sunday's interview served as a preview of how he could push back against criticism on the campaign trail.

The senator said he does not regret his vote, but said in hindsight it was a tough one to take.

"Well, I wish. You can always ask yourself, 'if I had known then what I know now, would have I voted differently,' and obviously as I said before I have great misgivings about how it was used," he said. "But I think when somebody comes to you and says, 'the economy is in a meltdown, the credit markets are frozen up,' these are all the experts on both sides of the aisle, Democrats and Republicans. That was a very compelling argument at the time and there was a lot of fear that if we didn't take steps it could have been disastrous for the country. And so in light of imminent financial meltdown, it was, I felt at the time, the right vote to make."

During the 2010 GOP primaries, Tea Party-backed candidates defeated GOP incumbents, such as Sen. Bob Bennett (Utah), who voted for TARP in Oct. 2008. 

The South Dakota senator recently said that he will decide whether or not to run for president early next year.