Sen. Jim DeMint (R., S.C.) sends out a warning to his Republican colleagues: Your job is on the line if you vote to raise the debt ceiling without backing a balanced budget amendment to the Constitution, as well as significant spending cuts and budget reforms (Cut, Cap and Balance):

“Based on what I can see around the country,” DeMint, R-S.C., said in an interview for the ABC News Subway Series, “not only are those individuals gone, but I would suspect the Republican Party would be set back many years.
“It would be the most toxic vote,” DeMint said. “I can tell you if you look at the polls, Democrats, Republicans, Independents, they do not think we should increase the debt limit.”
DeMint is not just talking political analysis here. He has a significant fundraising base and has shown a willingness to use his campaign money to support or oppose fellow Republicans.
DeMint will use that political muscle to oppose fellow Republicans who don’t stand firm on the debt ceiling issue. He said he will not support any candidate for Congress — incumbent or challenger — who does not sign a pledge promising not to vote for a debt limit increase without first passing a balanced budget amendment, making deep spending cuts and putting strict limits on future government spending. The same rule applies to presidential candidates.
“I don’t have many litmus tests, but this is one: Any candidate who doesn’t understand that we need to balance the budget should not be president of the United States,” DeMint said. “So, I’m looking for candidates to sign the pledge.”

More (with video) here.