Bachmann's campaign says the GOP presidential hopeful will sign the "cut, cap and balance" pledge, which says government should not borrow more unless there are big, immediate spending cuts to reduce the deficit, enforceable spending caps, and Congress passes a constitutional amendment to balance the federal budget.
Bachmann has avoided signing the pledge for several weeks, saying it didn't go far enough.
"I want it to go a little further, because I also think it needs to defund ObamaCare," she said on Tuesday night's program.
U.S. Sen. Jim DeMint said on CNN on July 6 that he was disappointed in Bachmann for not signing. DeMint has turned the pledge into a threshold test for 2012 presidential hopefuls seeking his support. Bachmann's campaign spokeswoman said that's one of the reasons she's signing the pledge here.
Bachmann would be the ninth GOP presidential candidate to sign the pledge. Five Republican governors have signed it, including South Carolina Gov. Nikki Haley.
Former Utah Gov. Jon Huntsman said last week that he won't sign because he opposes that type of pledge.
The U.S. House is expected to vote on the tea party-backed "cut, cap and balance" plan on Tuesday, though it's sure to stall in the Senate.
Bachmann will talk later Monday with religious leaders gathering at a Renewal Project event.
The group tries to keeps a low profile with meetings that are closed to the media, giving politicians a chance to share their views away from cameras and reporters.
"All of the speakers that I've heard seem ? to be almost like teaching or lecturing," Smtih said. "They want to be able to communicate, probably, in an unvarnished way."
Bachmann won't be alone among Republicans addressing the group in Columbia. Freshman Kentucky Sen. Rand Paul is speaking Monday night and presidential hopeful and former U.S. House Speaker Newt Gingrich will speak Tuesday.