WASHINGTON - A few weeks into her first term in Congress, Michele Bachmann stood around a radio booth as a news reporter described her as an evangelical Christian who had the potential to be "very outspoken" on social issues.

Bachmann approached moments later to inform him, "I'm also a tax attorney."

As the Minnesota Republican rises to prominence in the national Tea Party that meets this weekend in Nashville, the two sides of Bachmann's political persona have been fused into a mirror image of the newly charged conservative reaction against government spending and much of the rest of President Obama's domestic agenda.

But Bachmann's 11th-hour decision to bow out of the Tea Party's first national convention -- citing concerns about its for-profit model -- also reveals the fault line between the Republican hierarchy and the Tea Party's rank-and-file.

Bachmann was one of the few elected officials invited to this anti-establishment, small-government gathering. Her absence leaves the stage to kindred spirit Sarah Palin, the former Alaska governor who electrified down-home conservatives as the GOP's nominee for vice president in 2008.

But as an officeholder seeking reelection, Bachmann is one of the more pivotal leaders in the movement, a bridge between grass-roots Tea Party activists and a Republican Party debating whether to tack to the right or the political center.

It was Bachmann's name that was chanted by thousands of Tea Party protesters who rallied to her "emergency House call" last November on the steps of the U.S. Capitol.

GOP colleagues who once sought to muzzle the Minnesota Republican for inflammatory remarks on TV -- she once suggested that Obama and fellow lawmakers were un-American -- have been forced to re-evaluate her as the envoy of a populist movement born in church basements, at race tracks and gun shows across the country.

"Her voice doesn't just ignite the base or the Tea Party movement," said LeRoy Coleman, a spokesman for the Republican National Committee. "She's become a galvanizing voice in the Republican Party."

Dems see bumps in road

Democrats see Bachmann and her Tea Party allies as a delicious dilemma for the GOP. "There's no question that the Republican Party has been hijacked by the Tea Party movement," said Frank Benenati, a spokesman for the Democratic National Committee. "This is a movement that essentially has 'no moderates need apply' signs at their events and rallies."

Divisions over ideological purity already cost the GOP a congressional seat in New York last year, after Tea Party activists rallied around a Conservative Party candidate who ended up splitting the Republican vote.

Wary of rifts, GOP leaders have tried to reach out to Tea Party activists, whose conservatives principles make them natural allies. It's a mission for which Bachmann is singularly suited.

"The Tea Party is taking the Republican Party back to its roots," Bachmann said in an interview. "I'm grateful if I can take part in that message."

With no established national leader, the Tea Party sees itself as the vanguard of a new, bottom-up force in American politics. The unifying mission is to run big-government liberals out of Washington, with or without the help of the Republican Party.

The website for the Nashville convention, which started Thursday and runs through Saturday, describes the Tea Party Nation as a group of "like-minded people who desire our God given individual freedoms," inspired by the Founding Fathers, and who believe in limited government, free speech, the Second Amendment, the military and secure borders.

"It's organic, it's grass-roots, it's spontaneous," Bachmann said. "It's like popcorn popping up all over the country."

Obama loyalists, noting the Tea Party organizing of high-profile Republican figures such as former GOP House Majority Leader Dick Armey, don't see grass-roots.

"This is a grass-tops movement," Benenati said.

But it's not only Democrats who question the direction of the Tea Party movement and convention organizer Judson Phillips, a Nashville attorney with a shaky financial history of bankruptcy and tax liens.

Top-drawer prices

Delegates to the convention paid $549 a pop, not counting travel and lodging, to convene at Nashville's Gaylord Opryland Hotel for a weekend that has already caused division among the movement's haves and have-not-so-much types.

Reflecting a split with organizers of the for-profit event, some national Tea Party figures stayed away. One prominent Texas activist, Shane Brooks, posted a YouTube video urging a boycott of the gathering, suggesting a too-cozy relationship with the GOP and saying "Your Grassroots Revolution is being destroyed."

Another, Eric Odom of the American Liberty Alliance, which was listed as a "gold sponsor" of the convention, announced that his group would sit out the event, in large part because of the "$500 price tag" and questions over the event's financial oversight.

"Tea Party Nation has seen members come and go," Phillips said in a statement. "We have tried to deal fairly with our present and former relationships, however, not without some criticism. This criticism has been unfortunate and we believe, unwarranted."

The convention's business model, organizers say, is to make money and funnel it into conservative causes.

But the uncertainty over funding and profits wound up costing organizers their biggest elected draw: Bachmann.

She was not going to be paid, but had to worry about being part of a for-profit event whose revenues she could not control, with the potential for future conflicts of interest.

Citing the contradictory advice of House Ethics Committee lawyers, Bachmann canceled at the end of January. "I had no choice," she said. She was replaced by Steven J. Milloy, author of "Green Hell: How Environmentalists Plan to Control Your Life and What You Can Do to Stop Them."

Though she sent her regrets, Bachmann has hardly turned her back on the Tea Party movement, which overlaps with a broad base of individual contributors who helped her raise $1.5 million last year -- more than any other Minnesota politician now running for office.

"There's going to be a lot of money that comes in to oppose her," said Gary Borgendale, a conservative Christian activist in Minnesota. "The fortunate thing, from her standpoint, is that she does have a national platform, and she'll be able to raise the money to counter that."

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.