– Sen. Amy Klobuchar was back on familiar Midwestern ground on Saturday, making the case to Iowa Democrats that she has the best chance of defeating President Donald Trump in November.

“We win with the candidate that brings people with them,” Klobuchar told a large crowd of caucusgoers at a brewery in the Quad Cities, her first of a half-dozen “Get Out the Caucus” rallies across Iowa this weekend. Scattered around the room were supporters wearing green T-shirts that read, “Amy Klobuchar Will Beat Donald Trump.”

Facing the biggest test of her political career, the three-term Minnesota senator’s presidential ambitions depend on a strong showing Monday night when Iowans head to schools, churches, fire stations and other caucus sites.

Offering Midwestern pragmatism, stressing her humble roots and promising crossover appeal to independents and moderate Republicans, Klobuchar’s campaign message is built around the idea that she’s best positioned to win back the middle American battleground that went to Trump four years ago: Iowa, Wisconsin and Michigan.

“My profound advice to you is: we better not screw this up,” Klobuchar told the crowd in Bettendorf. Her campaign mantra: “I don’t want to be president for half the country, I want to be president for all of the country.”

The Iowa presidential caucuses, taking place in the shadow of a Senate impeachment trial, represent the opening volley in what promises to be a tumultuous 2020 election year. Trump, nearing the end of a turbulent first term that saw him impeached by the House, is preparing to take on one of the Democrats now sparring for momentum from Iowa.

For most of last year, Klobuchar trailed in Iowa polls behind four more well-funded, better-known competitors: former Vice President Joe Biden, Sens. Bernie Sanders and Elizabeth Warren, and former South Bend, Ind., Mayor Pete Buttigieg.

At her Saturday morning stop, Klobuchar could point to recent signs of momentum. In at least two Iowa polls since last Sunday, she leapfrogged both Warren and Buttigieg.

“I need your help,” Klobuchar said. “I am a candidate on the march, on the surge. I think you know that. I am a candidate, as they say, punching beyond my weight.”

A strong finish in Minnesota’s southern neighbor would provide a crucial springboard as the Democratic race expands quickly across the country in the coming weeks.

“You can’t overstate how important it is for her to do well in Iowa,” said Alex Conant, a Republican strategist in Washington and a native Minnesotan who held top jobs in the presidential campaigns of former Gov. Tim Pawlenty in 2012 and Sen. Marco Rubio in 2016. “Her whole campaign is predicated on the idea that she can do well in the Midwest, so if you don’t do well in the first contest, that happens to be in the Midwest — that would be detrimental.”

Klobuchar entered the race as an underdog: not well known nationally, from a “flyover” state (a term she has disparaged as a presidential candidate), and a moderate in a party whose energy seemed to be moving to the left. She’s raised considerably less money than her top four Iowa rivals, had less money in the bank by the end of last year, and of the four she’s the only one who has never led in any poll of the state.

But a slow build toward a strong showing in Iowa has been the Klobuchar campaign’s strategy from the beginning. The state’s caucusgoers have a history of hearing out lesser-known candidates, and of picking the eventual Democratic nominee.

“She really impressed me in the last debate,” Stacy Schempp, a Des Moines IT worker, said of Klobuchar. Schempp, 53, was in Waukee to see Biden speak on Thursday — while Klobuchar was stuck in Washington for the impeachment trial. Schempp said Biden is her current top choice, followed by Klobuchar.

“Sometimes from one day to the next it changes, where I lean,” said Schempp, who had not yet seen Klobuchar in person.

That’s not for lack of effort on the candidate’s part. Adopting an approach similar to what’s kept her consistently Minnesota’s most popular statewide politician, Klobuchar campaigned at least once in all of Iowa’s 99 counties.

Her campaign noted Klobuchar was the only “top-tier” candidate to visit all 31 Iowa counties that backed both Trump and Barack Obama in presidential elections — an echo of her own 2018 win in Minnesota, when she carried 42 Trump counties. That’s one of Klobuchar’s favorite stats on the stump.

Coming into this final weekend, Klobuchar’s campaign reported over 120 paid staff in Iowa working out of 19 offices across the state. She nabbed endorsements from 18 state legislators, though her moderate rivals landed bigger names: Biden has backing from Iowa’s two most recent Democratic governors and two of its sitting House members, while Buttigieg landed the state’s other Democratic U.S. House member.

But in a symbolic victory for Klobuchar, Kelly Shaw, the Republican mayor of Indianola, announced Friday that he will switch parties and caucus for Klobuchar.

A Klobuchar adviser said that caucus night organizing has focused in part on rural areas and Iowa’s northern swath, along the Minnesota border. The campaign also sees fertile ground in more blue-collar, older cities like Waterloo and Davenport, as well as suburban areas around Des Moines and Cedar Rapids.

It’s a sound but potentially risky strategy, said Christopher Larimer, a political-science professor at the University of Northern Iowa.

“It would have to a be a pretty good sweep” of rural areas, plus “finishing first or second in most of northern Iowa,” Larimer said.

“The big question for me is how does she do in the suburbs. I think she’ll do well in rural areas,” said Jeff Link, an Iowa strategist who worked for Obama’s winning Iowa caucus campaign in 2008.

Klobuchar’s message to Iowans and Democrats everywhere boils down to a few essential elements. She sells herself as a results-focused and pragmatic, with a tangible record of accomplishment in Washington. She also plays up the successful politician in a Midwestern state who does well even in the kind of rural precincts that have been shifting toward Trump and Republicans.

Klobuchar has eschewed the kind of transformative policy proposals — Medicare for All, student debt cancellation and free college — that characterize rival left-leaning candidates like Sanders and Warren. Klobuchar has promised more achievable goals, has a raft of detailed proposals that include a public option in health care and a massive infrastructure package funded by corporate tax increases.

“She gets things done. She’s got an actual record of accomplishment,” said Linda Nelson, a former state lawmaker and Iowa teacher’s union president from Council Bluffs who endorsed Klobuchar. “I served in office, I served in the minority like she does — it’s hard to get things done no matter where you are in government.”

On the campaign trail, Klobuchar offers frequent, extended critiques of Trump’s character and respect for democratic norms while promising she’ll be a president “for all Americans,” to use her frequent phrasing. She has honed a chatty style that mixes corny humor, frequent references to the “heartland,” talk of her own middle-class upbringing, public school education and family roots in organized labor.

“I know there’s a little rivalry between my state and Iowa. I get this,” Klobuchar said at a rally on a farm near Ankeny back in August, as she kicked off an extensive late-summer tour. “You pride yourselves on being first in corn, hogs and food on a stick. We’re first in peas, sugar beets and turkeys. There’s nothing Iowa likes to make fun of more than Minnesota being first in turkeys.”

Inconveniently for Klobuchar, the end game of her make-or-break Iowa campaign has seen her sidelined by the impeachment trial, forcing her to keep momentum building with surrogate appearances, tele-town halls, TV commercials. But as the top tier rivals ebb and flow, some see her odds improving.

“I said a long time ago she’d take third place. And I think she’s going to take third place,” said Jeff Shudak, a plumber and labor official from Council Bluffs who endorsed Klobuchar. “If she had a little more time, she’d probably do better.”

A ticket out of Iowa would bring new challenges and pitfalls. Klobuchar and her team would have to quickly ramp up fundraising to build a national infrastructure beyond next week’s New Hampshire primary. To date, it’s the only other state where Klobuchar has made significant time and money investments.

And a leap to the front of the pack would likely bring greater scrutiny. Recent questions about the controversial murder conviction of an African American teenager under Klobuchar’s watch as Hennepin County attorney could be amplified ahead of South Carolina’s primary, where black Democrats are a strong force.

And as Klobuchar rose in Iowa in recent weeks, criticism bubbled anew on social media about reports of her treatment of employees during her time in the Senate. Meanwhile, former New York City Mayor Mike Bloomberg, who’s largely bypassed Iowa and New Hampshire, passed her in a few recent national polls.

For now, though, it all comes down to Iowa.

“We haven’t seen one this wide-open in a while,” said Link, the Democratic strategist. “You’ve got five candidates that, I think, could all pull off a win.”

Star Tribune staff writer Torey Van Oot contributed to this report.