Minneapolis—This week Joe Klein had an interesting piece in Time about how the 2012 GOP presidential race is shaping up to be a battle between outsiders vs. insiders. Mitt Romney is the obvious insider of choice. Michele Bachmann, despite being a three-term member of Congress, is making a strong push to be the outsider who rallies the GOP faithful against the party establishment. Her appearance at the conservative RightOnline conference in Minneapolis today illustrated why she may be the dark horse to watch this cycle. (It’s also worth noting that the “grassroots” conference is run by the Koch Brothers–funded Americans for Prosperity Foundation.)

Bachmann drew enthusiastic cheers from the packed ballroom at the Hilton—complete with a gaudy blue and red stage with white stars—by talking up her opposition to Obamacare (she’s sponsored a bill to repeal it), the financial and auto bailouts, and raising the debt ceiling. “When are we going to buck up, when are we going to say no?” she asked rhetorically. Don’t be surprised if she leads the opposition among House Republicans to any impending deal between the Obama administration and the GOP leadership to raise the debt ceiling.

Bachmann’s making an unapologetic bid for the Tea Party vote, saying the movement represents far more voters than the “right-wing fringe of the Republican Party” and was “just gaining strength.” She asked the crowd to hold up a $1 bill to illustrate how the nation is drowning in debt. “42 cents on the dollar is borrowed money!” she said. Bachmann even talked about the unemployment rate among black and Hispanic Americans in front of the nearly all-white, predominantly middle-aged crowd. And the avowed social conservative kept the focus on jobs and the economy, despite ending her speech by quoting a passage of the Bible about the Philistines, reflecting the newfound center of gravity among the Republican base.

Unlike compromise candidates like Romney, who are considered more electable but have in the past taken positions at odds with the GOP base, Bachmann is an unapologetic Tea Party disciple. “Bachmann-Palin,” one crowd member yelled during her speech. Although a huge oil painting of Palin rested just outside the ballroom, Bachmann is positioning herself as a calmer, saner, more intelligent version of the Mama Grizzly. She seems far less crazy in person than she does on TV. Democrats would be smart not to underestimate her potential appeal. (Though she couldn’t escape a “glitter bomb” protester at the end of her speech.)

The GOP presidential primary is starting to look eerily familiar to the Democratic presidential primary in 2004. If Mitt Romney is John Kerry, the flawed yet formidable frontrunner, Michele Bachmann could become Howard Dean, the bomb-throwing hero of the grassroots. It’s insurgent vs. establishment all over again. As is usually the case, I’m guessing the establishment will ultimately prevail, although the attendees at RightOnline might have something to say about that.