In the race for the White House, Michele Bachmann is surging. A new Iowa poll, the first snapshot in the first-in-the-nation caucus state, found Bachmann statistically tied with front-runner Mitt Romney among likely Republican caucus-goers there.

Yet on Sunday, a day before Bachmann was to formally launch her campaign in her birthplace of Waterloo, Iowa, the Minnesota congresswoman faced the kind of scrutiny that comes to any leading presidential contender.

On “Fox News Sunday,” host Chris Wallace quizzed Bachmann on a series of apparent inconsistencies in her legislative record and personal background — from Medicare to government subsidies and earmarks to her opposition to same-sex marriage.

Then, as he wrapped up the interview, Wallace asked her: “Are you a flake?”

“I think that would be insulting to say something like that because I’m a serious person,” Bachmann retorted.

In the face of sharp questioning from Wallace, Bachmann appeared steely and calm, noting that she has “a titanium spine.”

On Monday, Bachmann refused to accept Wallace’s apology for using that word. “Those are the small issues. I’m focused on the big ones,” she told ABC News’ Jonathan Karl.

In the Fox News Interview, Bachmann said that by starting a Christian counseling business with her husband and helping lead the tea party movement in Washington she understands how to create jobs and has the necessary skills to turn the nation’s economy around.

But Wallace kept at it, asking Bachmann whether she recognizes that since she is now a presidential candidate she has to be more careful to not say the kind of “flaky things” that have earned her a reputation as a rhetorical loose cannon.

“Of course a person has to be careful with statements that they make, I think that’s true,” Bachmann said.

The scrutiny comes as Bachmann is breaking into the top tier of Republican 2012 hopefuls. Her breakthrough performance in the June 13 New Hampshire debate won her strong reviews. And a new Des Moines Register poll, released late Saturday, shows her with support from 22 percent of likely caucus-goers, behind only Romney at 23 percent.

The hotly-anticipated survey, which offered the first credible look this season at the race in Iowa, shows the former Massachusetts governor and Bachmann leading the crowded field. Businessman Herman Cain is third with 10 percent, while all other candidates were in single digits.

Former House Speaker Newt Gingrich and Rep. Ron Paul (Texas) each received 7 percent, while former Minnesota governor Tim Pawlenty received 6 percent. For Pawlenty, who has invested more time and money in Iowa this month than perhaps any other candidate, the poll was a sobering sign of the difficulties he appears to be having raising money nationally and breaking out in the early voting states.

For Bachmann, the poll’s release was good timing, as she hopes to build on that momentum with her Waterloo announcement Monday, to be followed by a campaign swing through New Hampshire and South Carolina.

But Bachmann will be competing for the spotlight in the Hawkeye State with another tea party heroine, former Alaska governor Sarah Palin. Palin, who has not said whether she will run for president, is scheduled to visit Iowa with her husband, Todd, on Tuesday to attend the premiere of a new documentary, “The Undefeated,” about her political career.

One of the factors that Palin may be weighing as she makes her decision is media scrutiny, as Bachmann faced Sunday. The Los Angeles Times published an investigative report Sunday that found Bachmann and her family have benefited personally from government aid even as the congresswoman campaigns against federal spending.

The newspaper found that the Bachmanns' counseling clinic has received nearly $30,000 from the state of Minnesota in the last five years, while a family farm in Wisconsin, in which the congresswoman is a partner, received nearly $260,000 in federal farm subsidies.

On the Fox show, Bachmann defended the payments, saying the counseling center payments were from the state, while the farm is owned by her father-in-law. She added that she does not support federal earmarks.

Wallace asked Bachmann to compare herself to the other 2012 contenders, including Romney. Although not specifically mentioning Romney, Bachmann said of herself: “I do what I say and I say what I do. I am a fighter for the cause. . . People recognize that I’m very sincere in what I say and I will fight.”

Later in the show, Bachmann attacked Romney for his refusal to sign a sweeping anti-abortion pledge by the Susan B. Anthony List. Although Romney once supported abortion rights, he now opposes them.

“President Romney,” Bachmann said, quickly correcting herself. “Not President Romney, Gov. Romney has a history of veering his position on this issue. I think clearly we need a candidate that is pro-life.. . .Mitt Romney has to say what he is, but I will say that if he is saying now that he is pro-life, this is a tremendous opportunity for him to demonstrate that by signing the Susan B. Anthony pledge, and I think it’s disappointing that he didn’t.”

Asked about the possibility of Texas Gov. Rick Perry entering the race and overshadowing her among tea party activists, Bachmann said she welcomes him and other late entrants.

“I think there’s room in the race for all sorts of candidates to get in,” Bachmann said.

In an appearance on CBS’s “Face the Nation,” Bachmann reiterated her opposition to same-sex marriage, but said states have a right to pass their own laws. She predicted that New York’s new law allowing gay marriages would be tested in the courts.

Asked by anchor Bob Schieffer whether she thought homosexuality was a choice, Bachmann demurred, saying she was not “running to be anyone’s judge.”

“I firmly believe that people need to make their own decisions about that,” Bachmann said. “But I am running for the presidency of the United States. I am not running to be anyone’s judge. And that’s where I’m coming from in this race.”

Bachmann also spoke personally of her Christian faith, telling Schieffer that she became a Christian when she was 16, that she “gave my heart to Jesus Christ” and has prayed to God about whether to seek political office.

“I pray believing that God will speak to me and give me an answer to that prayer,” Bachmann said. “That’s what a calling is.”

“Did God tell you he wanted you to run for the Minnesota state senate, or something like that?” Schieffer asked, referencing Bachmann’s earlier tenure as a state legislator.

“I prayed about that, as well,” Bachmann said. “And that’s really what that means. It means that I have a sense of assurance about the direction I think that God is speaking into my heart that I should go.”