In front of a standing room only crowd on a chilly late autumn evening in the state that holds the first primary in the Republican presidential nominating calendar, Nikki Haley was making her case.

The former South Carolina governor who later served as ambassador to the United Nations in former President Donald Trump's administration was arguing that she's more electable than her former boss in a 2024 general election matchup against President Biden.

"If you look at the national polls and you look at electability, you see that Trump is pretty much even with Biden. On a good day, he might be two points up. In every poll, we beat Biden by 10 to 13 points," Haley claimed at her Tuesday evening town hall at the historic opera house in Derry, New Hampshire.

Electability was a factor in the decision by Americans for Prosperity Action, the political wing of the influential and deep-pocketed fiscally conservative network founded by the billionaire Koch Brothers, to endorse Haley. 

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Nikki Haley draws a large crowd as she returns to New Hampshire

Former ambassador to the United Nations and former South Carolina Gov. Nikki Haley, a 2024 Republican presidential candidate, speaks at a town hall in Derry, New Hampshire, on Nov. 28, 2023. (Fox News - Paul Steinhauser)

The announcement Tuesday morning by the AFP Action, which has pledged to spend tens of millions of dollars and mobilize its formidable grassroots operation to help push the Republican Party past Trump, was a setback to Florida Gov. Ron DeSantis. 

Haley's enjoyed momentum in the polls in recent months, thanks in part to well-received performances in the first three GOP presidential primary debates

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She has leapfrogged DeSantis for second place in New Hampshire and in her home state, which holds the first southern contest. And she's pulled even with DeSantis in some of the latest polls in Iowa, whose caucuses kick off the GOP nominating calendar on Jan. 15.

But Haley and DeSantis remain far behind Trump, who continues to hold a commanding lead over the rest of the field as the former president makes his third straight White House run.

Donald Trump

Former President Donald Trump leaves the stage at a campaign rally Saturday, Nov. 11, 2023, in Claremont, New Hampshire. (AP Photo/Reba Saldanha)

The AFP Action endorsement should help Haley, whose lean campaign lacks the grassroots outreach and organizational strength that DeSantis can count on courtesy of the DeSantis-aligned super PAC Never Back Down.

The endorsement by AFP Action Haley comes with the group's powerful direct-mail and field operations, as well as a major ad blitz in the early voting states.

"Organizationally speaking – it's significant. This is muscle. This is political dollars and door knocking. It will help," Republican consultant Matthew Bartlett, who splits his time between New Hampshire and the nation's capital, told Fox News.

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Haley, addressing the crowd, asked, "How many of you are here to hear me for the first time?" 

A lot of folks in the audience raised their hands.

"There’s a lot of new people coming out and seeing Nikki," longtime GOP strategist Rick Wiley, who's steering Haley's operation in New Hampshire, told Fox News. Wiley said it was a sign that Haley's message is resonating.

"You can see the volunteers grabbing their information," Wiley said as he pointed to the crowd of first-time attendees. "We have RSVP’s and we’re going to put them to work."

Haley arrived in New Hampshire after drawing roughly 2,500 people to a campaign event Monday evening in her home state. 

Nikki Haley draws over 300 to a town hall in Derry, New Hampshire

Nikki Haley speaks at a town hall in Derry, New Hampshire, on Nov. 28, 2023. (Fox News - Paul Steinhauser )

While the audience of some 325 on Tuesday evening didn't compare to the South Carolina gathering, it was one of her largest crowds to date in the Granite State.

Among those attending was Republican state Sen. William Gannon, who endorsed Haley earlier this autumn.

Referencing the crowd, Gannon emphasized, "They like Nikki. She’s warm. She’s personable. We have candidates who could possibly win a primary. These people know that she can win next November." 

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Also in the audience were two former U.S. senators.

"She’s been a chief executive. She knows what kind of legislation is necessary to get an economy going. She’s a fiscal conservative," former Sen. John E. Sununu told Fox News. "I think if she can convey those concepts of letting people make decisions for themselves, getting the country moving forward and not looking back, then I think she’s going to do well in New Hampshire."

Sununu, the son of former New Hampshire Gov. John H. Sununu and the older brother to current Gov. Chris Sununu, said he remains neutral in the GOP presidential nomination race, but is considering endorsing and helping support a candidate.

"Like every other voter in New Hampshire, I’m excited about the primary," he said.

Former Sen. Gordon Humphrey told Fox News that he's "leaning toward Nikki Haley. I think she’s far and away the best of all the candidates."

Humphrey, a vocal anti-Trump Republican turned independent, pointed to what he described as Haley's "heavyweight experience" as a governor and in foreign policy and national security through her tenure as ambassador to the United Nations.

"She’s well-spoken. She has personality and charisma, sparkle, energy, dynamism," he touted.

While she's riding a political wave, Haley remains far behind Trump.

But Bartlett, who remains neutral in the primary battle, emphasized, "What is important – on a cold night like this, opening up the doors. Doing an old-fashioned town hall. Taking questions. Introducing yourself to voters. She is doing everything right… She’s got some granite heels, and we’re going to see how far they can climb the mountain here."

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