Former U.N. ambassador and 2024 presidential hopeful Nikki Haley speaks to Iowa residents during a visit in Spirit Lake, Iowa, on Dec. 9, 2023, ahead of the Iowa caucus. (Christian Monterrosa/AFP via Getty Images)

(WASHINGTON) — New Hampshire Gov. Chris Sununu plans to endorse Nikki Haley in the 2024 Republican primary on Tuesday night, according to sources familiar — a shake-up in a key early voting state where Haley and a few others have only weeks left to try and catch front-runner Donald Trump.

“I look forward to joining Nikki at her town hall this evening — it’s going to be a lot of fun!” Sununu told ABC News.

According to 538’s polling average, Haley is currently at nearly 19% in New Hampshire; Trump is at about 45%.

An endorsement from Sununu, a vocal Trump critic and popular figure in the state that prides itself on independent-minded voters, could help close that gap ahead of the state’s Jan. 23 primary.

“I have a lot of faith in Sununu,” said Christy Carlson, an undecided voter from Merrimack, New Hampshire. “So whoever he does get behind that endorsement means a lot to me. That’ll be big.”

Linda Webb from Wolfeboro, New Hampshire, echoed that: “I have an enormous amount of respect for the governor, and I am hopeful.” She said that she also hopes Sununu appears on the 2024 ticket somewhere with someone.

Back in June, Sununu opted out of throwing his own hat in the race for a White House bid because he felt a crowded field helped Trump. Since then, various Republican hopefuls have essentially been auditioning with Sununu for his endorsement and he narrowed his list down to three governors in the past few weeks: Haley, Florida Gov. Ron DeSantis and former New Jersey Gov. Chris Christie.

“If I make a decision to get behind a candidate, I’m gonna get behind a candidate. It’s not an endorsement. It’s really a movement that this country is looking for. They’re looking for a message movement,” Sununu said at a Haley event in November.

Haley, a former South Carolina governor and U.N. ambassador in the Trump administration, has seen her poll numbers steadily tick up in recent months, according to 538.

Still, she and other candidates like DeSantis trail Trump by double digits nationally and in various states, despite Trump’s legal troubles. (He denies all wrongdoing.)

Haley also recently won the backing of Americans for Prosperity Action, a powerful political advocacy group backed by billionaire Charles Koch.

DeSantis, for his part, has been endorsed by the governor of another early voting state, Iowa’s Kim Reynolds; and Trump has a slew of support including from House Speaker Mike Johnson.

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