In April 2005, Pamela Arnold wanted to talk to her state senator, Michele Bachmann, who was then running for Congress. A 46-year-old who worked at the Minneapolis College of Art and Design, Arnold lived with her partner, the famed Arctic explorer Ann Bancroft, on a farm in Scandia, Minnesota. Bachmann was then leading the fight against gay marriage in the state. She'd recently been in the news for hiding in the bushes to observe a gay rights rally at the Capitol. So when members of the Scandia gay community decided to attend one of Bachmann's constituent forums, Arnold, wanting to make herself visible to her representative, joined them.

A few dozen people showed up at the town hall for the April 9 event, and Bachmann greeted them warmly. But when, during the question and answer session, the topic turned to gay marriage, Bachmann ended the meeting 20 minutes early and rushed to the bathroom. Hoping to speak to her, Arnold and another middle-aged woman, a former nun, followed her. As Bachmann washed her hands and Arnold looked on, the ex-nun tried to talk to her about theology. Suddenly, after less than a minute, Bachmann let out a shriek. "Help!" she screamed. "Help! I'm being held against my will!"

Arnold, who is just over 5 feet tall, was stunned, and hurried to open the door. Bachmann bolted out and fled, crying, to an SUV outside. Then she called the police, saying, according to the police report, that she was "absolutely terrified and has never been that terrorized before as she had no idea what those two women were going to do to her." The Washington County attorney, however, declined to press charges, writing in a memo, "It seems clear from the statements given by both women that they simply wanted to discuss certain issues further with Ms. Bachmann."

Lots of politicians talk about a sinister homosexual agenda. Bachmann, who has made opposition to gay rights a cornerstone of her career, seems genuinely to believe in one. Her conviction trumps even her once close relationship with her lesbian stepsister. "What an amazing imagination," marvels Arnold. "Her ideology is so powerful that she can construct a reality just on a moment's notice."

Belief is the key to understanding Michele Bachmann, who announced her presidential candidacy during Monday's Republican debate. Herimpressive performance, which catapulted her close to the front of the presidential pack, surprised some, who perhaps expected her to be as inarticulate as Sarah Palin, to whom she's often compared. But in Minnesota, even those who don't like her politics say she shouldn't be underestimated. "The fact that she's not a heavy lifter, the fact that she's relatively unconcerned about the substance of legislation, does not mean that she's not crafty, that she's not intelligent and she's not fast," says former Minnesota Gov. Arne Carlson, a Republican. Her ideological radicalism should not be mistaken for stupidity.

On Monday, Bachmann didn't talk a lot about her religion. She didn't have to—she knows how to signal it in ways that go right over secular heads. In criticizing Obama's Libya policy, for example, she said, "We are the head and not the tail." The phrase comes from Deuteronomy 28:13: "The Lord will make you the head and not the tail." As Rachel Tabachnick has reported, it's often used in theocratic circles to explain why Christians have an obligation to rule.

Indeed, no other candidate in the race is so completely a product of the evangelical right as Bachmann; she could easily become the Christian conservative alternative to the comparatively moderate Mormon Mitt Romney. "Michele Bachmann's a complete package," says Ralph Reed, the former Christian Coalition wunderkind who now runs the Faith and Freedom Coalition. "She's got charisma, she's got an authentic faith testimony, she's a proven fighter for conservative values, and she's well known." She's also great at raising money—in the 2010 cycle, she amassed a record-breaking $13.2 million in donations. (Bachmann's office didn't respond to requests for comment.)

Bachmann, who was born in Iowa, was in high school in Anoka, Minnesota, when she was swept up in the wave of evangelical Christianity then surging through the country. "People were coming to the Lord left and right," she said in a recent speech. A pretty cheerleader, she was a member of student government and was elected to the homecoming court. But her family life was unsettled. Her parents divorced in 1970, and her father disappeared from her life and those of her three brothers. When she was in high school, her mother remarried, to a man with five children of his own. Working-class Democrats, the family went to a Lutheran church regularly, but it wasn't until she was born again at 16, she has said, "that the Gospel finally made sense to me."

After graduating from high school, Bachmann went to Israel with the evangelical youth group Young Life. Then, at Winona State University, she joined the evangelical Intervarsity Christian Fellowship, where she met her husband, Marcus Bachmann. At the time, the evangelical movement was not particularly political. Indeed, according to Randall Balmer, who is both an evangelical and a historian of American evangelicalism at Columbia University, it was the born again Jimmy Carter who first marshaled the era's newly awakened Christians. "He brings them into the political arena. There's no question about that," says Balmer. "And the great irony is that they turned so rabidly and rapidly against him four years later."

That's exactly what happened with Bachmann, who campaigned for Carter in 1976—she and Marcus even went to one of his inaugural balls—but soon tacked sharply rightward. A key moment in her political evolution, as for many of her generation, a was the film series "How Should We Then Live" by the theologian Francis Schaeffer, who is widely credited for mobilizing evangelicals against abortion, an issue most had previously ignored. A Presbyterian minister, Schaeffer argued that our entire perception of reality depends on our worldview, and that only those with the right one can understand the true nature of things. Christianity, he argued, is "a whole system of truth, and this system is the only system that will stand up to all the questions that are presented to us as we face the reality of existence." Theories or assertions from outside this system—evolution, for example—can be dismissed as the product of mistaken premises.

This accounts for some of the bafflement that occasionally greets Bachmann's statements. "Michele Bachmann says certain things that sound crazy to the general public," says author Frank Schaeffer, Francis Schaeffer's son and former collaborator. "But to anybody raised in the environment of the evangelical right wing, what she says makes perfect sense."

Bachmann honed her view of the world after college, when she enrolled at the Coburn Law School at Oral Roberts University, an "interdenominational, Bible-based, and Holy Spirit-led" school in Oklahoma. "My goal there was to learn the law both from a professional but also from a biblical worldview," she said in an April speech.

At Coburn, Bachmann studied with John Eidsmoe, who she recently described as "one of the professors who had a great influence on me." Bachmann served as his research assistant on the 1987 book Christianity and the Constitution, which argued that the United States was founded as a Christian theocracy, and that it should become one again. "The church and the state have separate spheres of authority, but both derive authority from God," Eidsmoe wrote. "In that sense America, like [Old Testament] Israel, is a theocracy."

Eidsmoe, who hung up the phone when asked for an interview, is a contentious figure. Last year, he withdrew from speaking at a Wisconsin Tea Party rally after the Associated Press raised questions about his history of addresses to white supremacist groups. In 2010, speaking a rally celebrating Alabama's secession from the Union, he claimed that Jefferson Davis and John C. Calhoun understood the Constitution better than Abraham Lincoln.

Reading Eidsmoe, though, some of Bachmann's most widely ridiculed statements begin to make sense. Earlier this year, for example, she was mocked for saying that the Founding Fathers "worked tirelessly" to end slavery. But in books by Eidsmoe and others who approach history from what they call a Christian worldview, this is a truism. Despite his defense of the Confederacy, Eidsmoe also argues that even those founders who owned slaves opposed the institution and wanted it to disappear, and that it was only Christian for them to protect their slaves until it did. "It might be very difficult for a freed slave to make a living in that economy; under such circumstances setting slaves free was both inhumane and irresponsible," he wrote.

After graduating from Coburn in 1986, Bachmann went on to get a degree in tax law from William and Mary School of Law in Virginia, while her husband studied psychology and counseling at Regent University, the school founded by Pat Robertson. His thesis was about the harmful effects of day care on children. "[T]he best interests of the public would be served if one parent did not work outside of the home unless it was absolutely essential," he wrote.

Nevertheless, when Bachmann's children were small, she worked at the IRS while Marcus got his Christian counseling business up and running. Finally, in 1992, she said, "I realized my lifelong dream, which was to be a full-time mother of children at home." That same year, she received her foster care license.

Bachmann often says she has "raised" 23 foster children. That may be a bit of a stretch. According to the Minnesota Department of Human Services, Bachmann's license, which she had for 7 1/2 years, allowed her to care for up to three children at a time. According to Kris Harvieux, a former senior social worker in the foster care system in Bachmann's county, some placements were almost certainly short term. "Some of them you have for a week. Some of them you have for three years, some you have for six months," says Harvieux, who also served as a foster parent herself. "She makes it sound like she got them at birth and raised them to adulthood, but that's not true."

Yet Bachmann clearly had some of her foster children long enough to enroll them in local schools, and it was through them that she got involved in school politics. While she taught her own children at home before sending them to private Christian schools, state law required foster kids to go to public school. Seeing their curriculum, she became convinced that "politically correct attitudes, values, and beliefs" had supplanted objective education. She helped found a charter school but soon left the board amid allegations that she was trying to inject Christianity into the curriculum. Then, in 1999, she decided to run for the local school board.

School board elections in Stillwater, Minnesota, had been nonpartisan affairs, but when Bachmann ran as part of a slate of five Republican candidates, culture war issues were injected into the race. "I remember being called by someone and asked where I stood on abortion," says former school board member Mary Cecconi. People felt that it was "sullying the process, that the partisan aspect doesn't belong at the local level," says Bill Pulkrabek, a Republican county official who helped organize Bachmann's slate. It was the only election she ever lost.

But the race served as her springboard into the statehouse. In 2000, she challenged incumbent state Sen. Gary Laidig, a moderate, for the Republican nomination. Bachmann, says Pulkrabek, had an extraordinary ability "to motivate activists and delegates to action." She won on the first ballot.

In the statehouse, Bachmann made opposition to gay marriage her signature issue. Both she and her husband, by all accounts her most trusted political adviser, believe that homosexuality can be cured. Speaking to a Christian radio station about gay teenagers last year, Marcus, who treats gay people in his counseling practice, said, "Barbarians need to be educated. They need to be disciplined, and just because someone feels this or thinks this, doesn't mean that we're supposed to go down that road."

In 2004, Bachmann gave a speech warning that gay marriage would lead to schoolchildren being indoctrinated into homosexuality. She wanted everyone to know, though, that she doesn't hate gay people. "Any of you who have members of your family in the lifestyle, we have a member of our family that is," she said. "This is not funny. It's a very sad life. It's part of Satan, I think, to say that this is gay."

She was clearly talking about her 51-year-old stepsister, Helen LaFave, who had lived with her partner, Nia Wronski, for more than 15 years. As Bachmann became the public face of opposition to gay marriage, her relationship with her stepsiblings grew strained. "Helen always liked Michele, always," says Linda Cielinski, one of Bachmann's other stepsisters. "They lived together as teenage girls. They were very close at that time." Bachmann's anti-gay activism, Cielinski says, "was a hit to the gut."

And so, in April 2006, when the Minnesota Senate judiciary committee met for a hearing on Bachmann's proposed constitutional amendment banning gay marriage, Helen LaFave, Wronski, and several relatives including Cielinski were all in the gallery. "I wanted Michele to put a face to this whole thing," says Cielinski. "These were family members she was hurting." They didn't intend to talk to the press—LaFave has always shied away from media attention—but journalists quickly learned who they were and surrounded them. (LaFave declined an interview request, citing concern about the effect of the controversy on her 87-year-old father, who is still married to Bachmann's mother.)

The ensuing brouhaha further tore at the family. In a Star Tribune story headlined "Bachmann, stepsister hold opposing views," Bachmann claimed that she'd polled her siblings and stepsiblings, and that six of the nine agreed with her. Her stepbrother Mike LaFave was horrified. "The reality was she hadn't taken a family vote count, nor would my family ever do such a thing," he says. "I just find it terrible that when Michele was taken by surprise by a question she wasn't prepared for, the first thing she did was throw not only my sister but her whole family under the bus."

Over the years, several letters from disgruntled Bachmann relatives have appeared in local newspapers, though they usually don't mention their relationship. "I have a suggestion for Michele Bachmann, R-Stillwater, since she's interested in watching gay people," Cielinski wrote in a letter published in the Pioneer Press in 2005. "Instead of hiding behind bushes with a security guard, go to the grocery store, a PTA meeting, ballgames, concerts, church, the movies, or take a walk around the lake…[T]hey are our friends and family members who have added so much to our lives." Bachmann never responded.

None of this is likely to sour her many devoted fans. Indeed, it's precisely her unwavering ideological commitment that endears her to them. "She's not afraid to say things that other people on the right are probably thinking, but they're just too wimpy to say," says Pulkrabek, who supports Bachmann's presidential ambitions. "She says these things and she promotes these views because she really believes them."