Manchester, New Hampshire — Before former South Carolina Gov. Nikki Haley took the stage at Hampshire Hills Athletic Club in Milford, New Hampshire, in early January, two state Republicans who had openly quarreled a year earlier over whether the 2020 election had been stolen from former President Donald Trump rallied the crowd in her support.

Retired Army Brig. Gen. Don Bolduc, a veteran of 10 tours in Afghanistan and one of Haley's first endorsements, was the first to speak, touted Haley's support of his failed 2022 Senate run and explained why he signed on to be her New Hampshire campaign chair. 

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"She was a mentor to me, and I realized I was making a lot of mistakes," Bolduc admitted to the audience of over 700. "It was made clear by a lot of people while I was running, 'The guy's not a politician.'"

New Hampshire Gov. Chris Sununu endorsed Haley in mid-December and has taken her around the state in hopes of defeating Trump in the state's first-in-the-nation primary on Jan. 23. 

"As the general said, [Haley is] the opportunity to get behind a candidate that unifies everybody together, that next generation of conservative leadership," Sununu told the crowd packed onto the basketball court in the athletic club. 

New Hampshire's open primary allows undeclared voters, who make up about 40% of the state's voting bloc, to participate in either party's primary election. It means Haley's path to victory depends on her appeal to that group, as well as the state's conservative base, which makes up about 30% of registered voters in New Hampshire. 

A seminal moment in Bolduc's 2022 race was his flip-flop over whether he believed the election had been stolen from Trump, an opinion shared by 19 other 2022 GOP Senate candidates, according to a CBS News analysis. 

"I signed a letter with 120 other generals and admirals saying that Donald Trump won the election and, damn it, I stand by [it], Bolduc said in an August 2022 debate against Democratic Sen. Maggie Hassan. 

"I'm not switching horses, baby. This is it," he added.

But weeks later, Bolduc backtracked, saying on Fox News that after he had "done a lot of research," he had come to the "definitive" conclusion that "the election was not stolen," though he claimed there was still fraud. 

Haley's comments about her support for election deniers have not always been accurate. In a 2022 interview with the "Today" show, she said that she would not campaign for candidates who had denied the results of the 2020 election.

"Everybody that I'm helping acknowledges the fact that the elections, you know, were real," Haley said.

However, Haley had campaigned for Bolduc both before and after his remarks claiming Trump had won the election. She also campaigned for or endorsed other GOP Senate candidates who cast doubt on the results of the 2020 election: Adam Laxalt of Nevada, Herschel Walker of Georgia, Mehmet Oz of Pennsylvania and Ted Budd of North Carolina. Only Budd ultimately won his race. 

Sununu was one of Bolduc's most vocal critics, calling him a "conspiracy-theorist-type candidate." In the Senate Republican primary, Sununu backed Bolduc's challenger in the race, Chuck Morse. 

In response, Bolduc called Sununu a "Chinese Communist sympathizer." But after Bolduc won the primary, Sununu eventually supported him in the general election.

"Governor Sununu and I agreed that the comments we made about the 2022 race were put to bed at the Republican breakfast after the [2022] primary," Bolduc wrote in a text message to CBS News. "We both agreed that campaigns get sporty, things get said, and when the dust settles we must unite for the greater good."

The Haley campaign has touted the endorsements of both men, featuring them in separate ads in recent weeks. Sununu is a popular governor who won reelection in 2022, decisively winning traditionally Democratic areas like Manchester, Nashua and Merrimack, as well as the Republican-leaning parts of the state.

Haley, for her part, has sought to appeal to both independents and Republicans on issues like abortion, mentioning the need to find a national "consensus" on an abortion ban, but also pledging to not judge anyone for being pro-abortion rights. 

Trump won the 2016 GOP primary in New Hampshire and he lost the state by less than 3,000 votes in the general election, although President Biden had a more decisive victory of nearly 50,000 votes in the state in 2020. Trump leads recent polls for the GOP primary this year, but Bolduc and Sununu both hope voters across the state are ready to move on in the name of selecting a unifying nominee. 

Bolduc's involvement in Haley's campaign isn't without risk. A longtime New Hampshire political operative told CBS News he was polled via text by the Haley campaign on Bolduc's favorables, suggesting that Haley's team has some concerns about Bolduc's appeal to GOP primary voters, particularly independents.

"I wonder if they've calculated the paradoxical effect of Bolduc, and if they calculated the net loss percentage of putting him up front," the operative added. "They'll realize at some point after the fact they made a mistake here."

"Nikki is winning over Granite State voters of all sorts, from former Trump supporters to grassroots Republicans to Independents. That's the winning formula for beating Joe Biden in a landslide, which is what all the polls show she will do," a Haley spokesperson told CBS News.

Trump's campaign declined to comment on the dynamic between Bolduc and Sununu. 

"Like Nikki, I believe that President Trump was the right president in 2016. I also supported Trump in 2020," Bolduc told CBS News. "Unfortunately, President Trump over the last four years has not moved forward and has become more divisive. He is incapable of doing the most important thing for all Americans and that is uniting the country."

"If America does not unify, we will destroy ourselves from within," Bolduc warned, calling on far-right Republicans, moderates, and further-left Democrats to come together to support her. "We must come together for the future of our children and grandchildren."

In:
• New Hampshire
• Donald Trump
• Nikki Haley