DES MOINES, Iowa — Republican Michele Bachmann’s presidential campaign fell just as quickly as it rose. Now, she’s looking to Iowa — at the expense of other early voting states — to get back on track.

It’s a strategy of necessity for the Minnesota congresswoman. A victory in Iowa this winter would keep her afloat in the GOP nomination fight; a loss would almost certainly end her bid.

“We know that when Michele is in Iowa, she wins,” said Bachmann’s Iowa campaign chairman, Kent Sorenson. “If she’s here, she’ll win Iowa.”

That explains why, starting this weekend, Bachmann plans to campaign almost exclusively in the state as she tries to reassert herself in a race that’s become a two-candidate contest between Texas Gov. Rick Perry and former Massachusetts Gov. Mitt Romney.

She’s in a far different position than she was earlier this summer when she entered the race and seemingly overnight began hovering atop state and national public opinion polls. In August, she rode that wave of popularity to an Iowa straw poll victory. But that same day, Perry became a candidate. He quickly filled the role of the GOP field’s insurgent outsider, stalled Bachmann’s momentum and infringed on her base of support.

Since then, Bachmann has faced criticism from voters and activists for appearing too scripted. She’s also shuffled her top campaign leadership. And she found herself eclipsed in Wednesday’s debate in California after figuring prominently in previous ones and winning praise for her poise.

Her newfound strategy calls for an intense focus on Iowa, where she already has a strong organization and a natural base of support with evangelical Republicans, home-school advocates and tea partyers.

The hope among Bachmann advisers is that an Iowa victory could propel her to the South Carolina primary, where Republican voters resemble Iowa’s heavy segment of Christian conservatives. She spent a chunk of the past month in the state, as well as in Florida, courting tea party activists and other conservatives.

But the renewed focus on Iowa — she plans to spend much of the next five months there — means Bachmann is likely to bypass Nevada’s under-the-radar caucuses and remain scarce in New Hampshire, where she has almost no organization in place for the first-in-the-nation primary.

The next few weeks represent a critical period for Bachmann. She is hoping to right her campaign and take advantage of a time when Perry is facing heightened scrutiny that’s certain to come with more debates this month and the end of his first fundraising quarter at the end of September.

Perry too is organizing aggressively in Iowa, and aides to Romney, who is not campaigning aggressively in the state, say he may step up his Iowa presence to confront Perry sooner in the nominating chase. That could complicate Bachmann’s effort to dominate Iowa at a time when she is adjusting to new campaign leadership.

Ed Rollins announced Sunday he was stepping aside as Bachmann’s campaign manager and into an advisory role. Rollins’ deputy, David Polyansky, also quit the campaign after being passed over to take over the day-to-day management.

Republican observers viewed the moves as a reaction to Bachmann’s fade in polls. She has slipped to the low single digits in national polls and now trails Perry in Iowa surveys.

The staff shake-up provides Bachmann with an opportunity to shed the image of an over-managed celebrity.

Some Iowa Republicans recently criticized Bachmann for staying on her campaign bus during a county GOP dinner while Perry was speaking. The episode fed a budding narrative that Bachmann pays more attention to stagecraft than mingling with activists, something that doesn’t sit well with Iowans used to politicians doing retail campaigning.

“Her campaign has to drop this rock-star motif,” said Judd Saul, an undecided Iowa Republican who attended the event last month. “She won the straw poll but needs to dig in, shake our hands, get to know us.”

Other would-be backers have grown frustrated by what they view as a sound-bite campaign.

Retired nurse Ellen Harward, a Myrtle Beach Republican, was attracted to Bachmann after seeing her at a late June rally. But by this week, Harward had not decided whether she would back her in the South Carolina primary, the first Southern contest.

“She’s starting to sound like a broken record,” Harward said. “If she could come out and show something that would set her apart from everyone else, it would make people start looking at her in a different way. It might give her some oomph her campaign needs.”

The return of Congress, which has spending and economic issues on its plate, also could give Bachmann a chance to reclaim the spotlight and rekindle the populist spark that built her into a surprise contender. Over the summer, she used her role as a vocal critic of the Obama administration and the GOP leadership in Congress to rail against deal-making in Washington, especially on raising the debt ceiling. She opposed it.