Sen. John Thune (R-S.D.) said a third party could emerge as early as 2012 if Republicans stray from their principles.
Thune, a potential presidential candidate in 2012, predicted that if Republicans win majorities in Congress but don't follow through on their promises, it could cause a third party built in the shape of the Tea Party movement to take off.
"I will say this: If we do not govern according to our principles and if we don't follow through on the things we say we're going to do, I think there will be a third party in this country," the fourth-ranking Senate Republican said on C-SPAN's "Newsmakers" program, set for broadcast this weekend.
Thune said that Republicans could be given another chance to govern after voters handed Democrats majorities in the House and Senate in 2006, which they've held since then.
"If we don't govern accordingly, I think you're going to see a third party in this country," he said. Thune suggested that such a third party might be closely aligned with the Tea Party — the crop of conservative grassroots activists who've had a heavy influence on politics this election cycle.
Such a third party could come soon, "conceivably" as soon as 2012, if the GOP were to win control of the House or Senate, Thune said.
Thune, like many other Republicans, has sought to build off of the momentum that movement has brought to the elections this time around, though he and many other possible Republican candidates for president have given more to establishment Senate candidates than those backed by the Tea Party.
Thune explained that the Tea Party movement didn't want to be seen as a fundamental part of the GOP.
"I don't think the Tea Party wants to be adopted," he explained. "I think they view themselves as a very independent movement."