Rep. Michele Bachmann has become the latest high-profile conservative to bag the rapidly unraveling Tea Party Convention in Nashville next week.

The Minnesota Republican, who has become something of a heroine of the Tea Party movement, decided Thursday morning that she is cancelling her appearance at the Gaylord Opryland Hotel next Friday, where she was scheduled to be a breakfast speaker. Bachmann's office cited the same concerns that other Tea Party activists have voiced about the first-of-its-kind national gathering: namely, the for-profit model of organizer Judson Phillips, a self-described "small town lawyer" with a history of financial problems. Phillips has announced that the $549-a-head convention featuring Sarah Palin is sold out. But Tea Party critics and allies alike have been asking questions about what Phillips plans to do with the money. Concrete answers have been in short supply, and in the end it looked like too big a risk for any public office holder. "We're out," said Bachmann spokesman Dave Dziok. "It comes down to conflicting advice as to how these profits are going to be used after the fact. We'd rather err on the side of caution than do it and find out it's improper... with somebody saying 'they're using the money from an event you were at to support this and this,' which comes as a direct conflict with what you're doing as a member of Congress." One of the only other elected officials scheduled to appear, Rep. Marsha Blackburn, R-Tenn., also has backed out, citing similar concerns. Both Blackburn and Bachmann sought legal guidance in recent days from lawyers in the House Ethics Committee. According to Dziok, they got "conflicting advice." That was enough to put on the brakes. No word yet on Palin's plans, but as a former government official, she may not face the same legal questions. Unlike Palin, who is reportedly getting a $100,000 speaking fee, Dziok said Bachmann was not getting any money for her speech. Update: In a formal statement, Bachmann's office made clear that her decision doesn't mean she's turning her back on her Tea Party supporters:

"Some will want to portray her withdrawal as a repudiation of the Tea Party Movement, but that couldn't be further from the truth. Congresswoman Bachmann remains encouraged by all Americans, regardless of political party, who are concerned about this nation's future and dwindling prosperity, and continues to be inspired their passion."