As it happened, Warren was holding a town hall event here, and Marttila won a raffle that allowed her to ask the final question of the day. She began by describing what she had learned across 6 miles of door knocking.

“I talked to a lot of people today who really, really like you,” she said. “They might even like you the best. But they are really scared to vote for who they like the best. Because they’re worried that not enough people feel the same way.”

Then she posed perhaps the most urgent question facing Warren in 2020.

“What do we do,” she asked, “to give people the courage to vote for who they like the best?”

Warren covered little new ground that day, talking about “running from the heart” and how “fear doesn’t win.” But Tuesday night, before a national debate audience and with time running short to reignite her candidacy, Warren delivered her most emphatic answer to date about her electability: She cited her own electoral success compared with her male opponents and the political gains made by other female candidates, as well as her determination to unify a sometimes fractious Democratic Party.

“That’s my plan,” she said Tuesday night, in an echo of her signature line, “and that is why I’m going to win.”

But the fear, reflecting doubts held by many moderate Democrats, is that the cost and scale of her swelling list of policy plans will scare off voters in the general election, according to interviews with dozens of voters, her own surrogates and endorsers and Democratic officials in the state. Then there are the worries about her ability to unite the party against President Donald Trump as a liberal Democrat and the sexism she would face from some voters.

If Warren was once the Democratic candidate to beat in Iowa, lifted by the kinetic energy of her crowds and a sprawling campaign infrastructure that far exceeded those of her rivals, she is now trying to allay the second thoughts that some voters have about her sweeping agenda — especially “Medicare for All” — and how well it would sell against Trump.

“As more became known about her plans, the original excitement was offset by skepticism about the practicality of her positions,” said Jeff Fager, the Democratic chairman in Henry County in southeastern Iowa.

Warren would hear it herself in her famed “selfie” lines. Her organizers would hear it as they canvassed. And her rivals have relentlessly sought to exploit a vulnerability that she had left largely unanswered.

Deepening Warren’s challenge in Iowa: She has been outmatched on television and outpaced online, and others have caught up to her in sheer organizational size. In only a single week has she been the top television advertiser in Iowa, for instance; Pete Buttigieg has spent more than twice as much on the airwaves. And among the top-tier candidates, Warren has devoted the smallest share of her overall Facebook budget to Iowa — only 7%.

Yet with less than three weeks remaining until the Iowa caucuses, Warren, of Massachusetts, is still within striking distance. A poll late last week from The Des Moines Register showed her at 17% support, narrowly trailing Sen. Bernie Sanders of Vermont, her ideological rival, but slightly ahead of former Vice President Joe Biden and Buttigieg, the former mayor of South Bend, Indiana.

For weeks leading up to Tuesday’s debate, Warren’s supporters had agitated, publicly and privately, in Iowa and beyond, that she had not sufficiently prosecuted the argument of her electability compared with her rivals, many of whom have framed their bids around how they would beat Trump.

Sen. Amy Klobuchar of Minnesota has cast herself as a Midwestern moderate; Buttigieg has portrayed himself similarly but also as a next-generation candidate; Sanders says he can best win back working-class voters; and electability is at the very core of Biden’s campaign.

Electability is an amorphous concept that intersects with gender and race and can disadvantage those who don’t fit the mold of all but one past president: white men.

“The people who want a strong male leader who acts like a football coach are probably never going to vote for her,” said Nancy Gaub, 65, from Fairfield, Iowa, who attended a Warren event in December.

On Tuesday, Warren came to the Des Moines debate armed with a fresh answer to that criticism. “Look at the men on this stage,” she said. “Collectively, they have lost 10 elections. The only people on this stage who have won every single election that they’ve been in are the women.” She went on to note that she alone had beaten an incumbent Republican in the last three decades.

Her pitch as a unifier, however, may have suffered in the moments after the debate when cameras caught her apparently refusing to shake Sanders’ outstretched hand.

Longtime friends and allies, Sanders and Warren have sparred in recent days over whether he told her in a private meeting in late 2018 that he did not believe a woman could be elected president. She said he did make the remark; he has denied it.

Running as a “unity candidate” capable of bridging the party’s ideological division has also left Warren sandwiched between two politicians in Sanders (on the left) and Biden (to her right) with durable bases of support.

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And though Warren is known for her plans, her decision in November to release her own sprawling Medicare for All proposal has particularly damaged her standing with moderates who balk at the plan’s $20.5 trillion cost and resist the idea that it could cause them to lose their private insurance, according to interviews with voters.

“Elizabeth Warren assumed wrongly that everyone knew how great Medicare for All would be and how feasible it is,” said Claire Celsi, a state senator who has endorsed Warren. “But her lack of an explanation of how she was going to pay for it made people skeptical.”

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Warren’s supporters believe her early investment in Iowa field organizing will help her to the finish. A frenetic series of events last weekend offered a sneak peek of sorts at the organizing muscle of her campaign here, as Warren campaigned with one of her national co-chairs, Rep. Katie Porter of California, in one city and a former presidential rival, Julián Castro, in another. Her husband cut the ribbon on a new office in Ankeny on Monday, and a group of black women who have endorsed her led a weekend canvass kickoff in Des Moines.

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But there has been some grumbling in the western part of the state about Warren’s relative absence. She has not been to northwestern Iowa since August, and she has ventured west of the Des Moines area only once in that time.

In December, Warren scored the coveted endorsement of Art Cullen, Pulitzer Prize-winning editor of The Storm Lake Times, which is based in the northwestern part of the state. When she called to thank him for the endorsement, Cullen said, he gave her an earful on why she needed to show up more often.

“I’ve not understood why she’s not been present in Iowa as much as she should be,” Cullen said in an interview. “Specifically, I mean western Iowa.”

Warren has remained relatively absent from the airwaves — a crucial medium for appealing to older voters in particular — even as her rivals have stepped up their television spending. Through Monday, her $3.7 million in Iowa television ads is only a fraction of her opponents’ advertising: less than half what Buttigieg has spent (nearly $8 million), and barely more than half of Sanders’ spending ($7.2 million), according to data from Advertising Analytics.

“On the ground, based on what I’ve seen, Warren’s campaign is very focused on the person-to-person type of campaigning,” said Sandy Dockendorff, a former Democratic chairwoman in Des Moines County who has endorsed Warren. “It’s not all wholesale ad-based.’’

Warren has been similarly outpaced on Facebook, a critical digital platform, where she has spent only the fifth most in the field, according to data covering the last 90 days. And while she has devoted only 7% of her Facebook spending to Iowa during that time, Buttigieg has poured more than 20% of his Facebook budget into ads in the state; Sanders is at 11% and Biden at 14%. (Andrew Yang spent a remarkable 62% here.)

At an event with voters in Marshalltown on Sunday, Warren was asked about the avalanche of ads shaping the race. “The one thing that beats a TV ad, the one thing that beats a Facebook ad, the one thing that beats fake news is you,” she said. “It’s you. It’s the face-to-face. This, to me, is what Iowa is all about.”

As much as Iowa holds the key to unlocking her 2020 ambitions, Warren’s campaign has sought to invest heavily beyond the state. It has staff on the ground in more than 30 states, and every Warren aide in the four early contests — Iowa, New Hampshire, Nevada and South Carolina — has already received a redeployment assignment for Super Tuesday or beyond.

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But almost everywhere, Warren has faced questions of how she would match up with Trump. In Iowa, Democratic voters have consistently said they put greater emphasis on a candidate’s chances of beating Trump than on finding one who shares their values — by a 2-1 margin for most of 2019 and by 55% to 40% in the latest Register poll.

“I am ready to poke my eyes out about whether to support the candidate most likely to be a moderate and win the election,” said Dea Epley Birtwistle, 62, a school social worker who attended Warren’s event in Mason City.

“It’s going to come down to that issue of winnability,” she said. “But I want to not feel like I sold my vote.”

This article originally appeared in The New York Times .