Jeff Haynes/Reuters

WATERLOO, Iowa – On the eve of her presidential announcement, Michele Bachmann returned home to the city of her childhood on Sunday to reconnect with her Iowa roots, which she hopes to parlay into an advantage in her quest to win the Republican presidential nomination.

“I need you!” Ms. Bachmann said. “I came here because it’s all about Iowa. You will be the ones who will determine who will lead this great nation in the future. That’s your choice.”

A few hundred people gathered inside the Electric Park Ballroom on the grounds of the National Cattle Congress to welcome Ms. Bachmann, who is set to formally open her candidacy here on Monday morning. She lived in Waterloo until age 12, when her family moved to Minnesota.

Ms. Bachmann introduced her Iowa family – many of whom, she confessed, are Democrats – and said that her connections in the state that opens the Republican presidential nominating contest early next year would elevate her above the field of candidates. She said her ascent would begin at the Iowa Straw Poll on Aug. 13.

“It’s a big deal,” Ms. Bachmann said, urging people in the audience to descend on Ames for the Republican event that serves as a test of a campaign’s organization that can make – or break – presidential aspirations.

The rally on Sunday evening underscored the degree to which Ms. Bachmann intends to use her Iowa biography to try and distinguish her from other Republicans in the race. A strong showing at the straw poll, she said, would send a clear message about the seriousness of her candidacy.

Before flying to Waterloo, Ms. Bachmann made an appearance on “Fox News Sunday,” where the program’s host, Chris Wallace, bluntly asked: “Are you a flake?”

“That would be insulting to say something like that,” she replied, smiling as she offered a list of her professional accomplishments, including her work as a federal tax attorney, a business owner, a state senator and a member of Congress.

She was greeted with a standing ovation as she entered the ballroom to loud strains of “Walking on Sunshine.” She told the crowd that she had spent the afternoon visiting the spots of her youth: Dairy Queen, the First Lutheran Church and her family’s home on East Ninth Street. She referred again and again to her Iowa upbringing, which she said would be the core of her candidacy.

“This is what we need more of,” Ms. Bachmann said. “We need more Waterloo. We need more Iowa. We need more closeness, more family, more love for each other, more concern for each other, more taking that sensibility that we grew up knowing. It’s not too late. I want you to be encouraged.”

Dave Ripley, a retired teacher from Charles City, said he was pleased that Ms. Bachmann is entering the presidential race. His blue T-shirt – an image of President Obama’s old campaign logo that said “GONE Jan. 20, 2013” – telegraphed his political views. He said he was still surveying the Republican field, but said the Iowa roots of Ms. Bachmann would not sway him.

“It’s too early to know,” Mr. Ripley said after the event concluded, as Ms. Bachmann shook hands into the night. “But she’s on the right side of every issue.”