DERRY, N.H. — She’s been the candidate with “a plan for that.” A firebrand who emphasizes why she’s “in this fight.” Now in a muddled race with no clear front-runner, and as barbs fly among the top contenders, Elizabeth Warren is staking her claim to being a unifying force for a fractured Democratic Party.

That pitch faces a critical test in New Hampshire, where many voters question Warren as the messenger and tell NBC News they see the Massachusetts senator as more of a combative figure who will challenge the system than one inclined to bring factions together.

In television advertisements and campaign events, Warren has pressed the case that she’s best-positioned to bring together warring party factions as a populist left seeks to wrest power from a business-friendly establishment. That message earned her a middling third-place finish in Iowa, raising the necessity of a strong performance in her home state's neighbor of New Hampshire, where the Democrats debated Friday.

But to many Democrats, the message is difficult to square with Warren’s central pitch of imposing “big, structural change” by taking on wealthy and entrenched interests who she says have a corrupting influence on both parties. After all, those entities — that count moderate Democrats, including lawmakers friendly with Wall Street, among their ranks — won’t back down without a fight.

“I love Elizabeth, but she’s got a little bit of an edge,” said Chester Lyons, who drove from Andover, Massachusetts, to Merrimack, New Hampshire, to see Pete Buttigieg, and plans to vote for the former mayor of South Bend, Indiana. “Right now, what I think the country needs is that healing capability to bring everybody together.”

On the other end of the spectrum, some left-leaning voters in New Hampshire this week said they felt alienated by Warren’s softening on "Medicare for All," which she said she’d defer to her third year in office while offering a separate 100-day plan that makes government insurance optional. The move was intended to be a bridge between the two sides of a contentious intraparty debate.

"She was my backup. But now I don't have a backup,” said Raphael Fraga of Andover, Massachusetts, who plans to vote for Sen. Bernie Sanders, I-Vt. “She lost my trust."

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It was a clear demonstration of the challenge posed by the delicate balance Warren's trying to strike with voters.

"I don't know if they necessarily see her [as a uniter], but I think that's probably her best move at this point," Christopher Galdieri, a political science professor at Saint Anselm College, said. "There is some tension there, because she has to basically be saying 'the fights that I'll be undertaking are ones that every Democrat can get behind.'"

"There are a lot of older, moderate, conservative Democrats who are a little wary of" her plans such as replacing private health insurance with a government-run plan or making public college free, he said.

The tension was evident in her pitches this week. At a town hall Tuesday in Keene, New Hampshire, when Warren presented herself as someone who can “win the Democratic Party and pull it together,” pleading with voters that “we can't have a repeat of 2016” — a reference to party divisions that many Democrats believe cost them the presidency.

But she also indicated she would challenge segments of her party, which she has been known to do — whether it’s taking on President Barack Obama on trade deals or criticizing moderate Democratic senators for backing legislation to deregulate small or midsize banks.

"We're the Democrats. We should be the party on the side of hardworking people," Warren said Friday at the debate, arguing that her sweeping anti-corruption plan can attract Republicans and independents to rally against powerful elites. "They hate the corruption as well."

Illustrating her complex relationship with the popular ex-president, Warren rolled out an ad this week touting Obama's praise in 2010 for her work setting up the Consumer Financial Protection Bureau.

Warren supporters hold up her two messaging points as plausible.

"I think you can unite people behind a cause and fight for what you believe in,” Camille Smith of Hampton, New Hampshire, said.

Joyce Sullivan of Chester, New Hampshire, who came to see Warren in Derry and plans to vote for her, agreed. "My hope is that she would be a uniter but she seems more of a fighter now.”

Warren’s shift to a message of unity was borne of both necessity and opportunity. It began last month as Sanders was consolidating the left with endorsements from progressive stars like Rep. Alexandria Ocasio-Cortez, D-N.Y., and advocacy groups such as the National Nurses United and the Sunrise Movement. Meanwhile, former Vice President Joe Biden and Buttigieg were attracting many moderate voters as they offered a message of national healing and policy platforms that took the path of least resistance.

As that was happening, Warren operatives noticed an interesting trend in the final weeks before voting: she consistently ranked as the top second-choice preference for Democrats in surveys, indicating a broad potential with competing wings of the party. And in Iowa specifically, one campaign aide said, among Iowans likely to caucus for Warren, those who caucused in 2016 were a 50/50 split between Sanders and Hillary Clinton.

And so the “unity” pitch seemed promising for an electorate that was desperate to win. When Warren was asked Thursday at an evening town hall here about how voters see her — as a fighter, or as the unifier she’s recently pitched herself — she said they’re not mutually exclusive concepts.

“Fighting for people against giant corporations ... that’s something Democrats and Republicans understand,” she said, arguing that issues of economic inequality make Americans of all partisan stripes angry.

Helen Grembowicz of Milford, New Hampshire, said she's undecided but has doubts about Warren.

"I like Elizabeth," she said. "I don't really see her as a uniter."