WASHINGTON — He calls her “fake MAGA Karoline” from “the swamp.” She calls him a “Fauci foot soldier” and a “pharma bro.”
A congressional primary in New Hampshire between two young, conservative former Trump staff members has divided MAGA Republicans and the party’s leaders in the House, devolving into a bitter, expensive battle over who carries the mantle of Trumpism.
The race, in a highly competitive district currently held by a Democrat, will be decided on Tuesday. Its outcome could determine whether Republicans have a chance at flipping the seat in the midterm elections in November as part of their drive to reclaim the House majority. The contest has also highlighted a power struggle in the party ranks that will shape what that majority might look like if Republicans take control.
Matt Mowers, 33, who worked on Donald J. Trump’s 2016 campaign, served him at the State Department and was endorsed by the former president in an unsuccessful bid for the same congressional seat in 2020. Mr. Mowers entered the race last year as the presumed front-runner against Representative Chris Pappas of New Hampshire, who is one of the most vulnerable Democrats in the country in this election cycle.
Mr. Mowers is viewed as a strong candidate with high name recognition in the state’s First Congressional District; he drew favorable coverage from right-wing news outlets like Breitbart and a well of endorsements from powerful conservative figures. They include Representative Kevin McCarthy of California, the minority leader; Representative Steve Scalise of Louisiana, the No. 2 House Republican; Representative Jim Banks of Indiana; as well as Corey Lewandowski and David Bossie, the former Trump campaign managers.
But despite all that, Mr. Mowers is facing a strident and surprisingly fierce challenge on his right from Karoline Leavitt, 25, a former assistant in Mr. Trump’s White House press office. She is backed by a host of hard-right Republicans in Congress, including Senator Ted Cruz of Texas and Representatives Lauren Boebert of Colorado, Jim Jordan of Ohio and Elise Stefanik of New York, the No. 3 House Republican.
The race has turned less on any ideological divide between the candidates, who have few discernible differences on policy, than on style and tone. Where Mr. Mowers opts for nuanced, carefully worded statements, Ms. Leavitt almost always reaches for the most extreme and provocative ones.
Her success at turning the primary into a neck-and-neck competition has underscored how in the current Republican Party, fealty to Mr. Trump is not always enough on its own to sway voters. What increasingly matters is a willingness to mimic his tactics, by adopting inflammatory language and making the most incendiary statements possible.
“Maybe in part because Leavitt came out of the White House press operation, it’s like a second language to her,” Dante J. Scala, a political science professor at the University of New Hampshire, said of her ability to channel the style and rhetoric of the MAGA movement. “Her campaign has been the whole package, and that’s put Mowers to the wall.”
Take, for instance, Mr. Trump’s lie that the 2020 election was stolen. When pressed about whether he agrees, Mr. Mowers has said he harbors concerns about voting “irregularities around the country.”
That was too wishy-washy for Ms. Leavitt, who repeats Mr. Trump’s falsehoods unequivocally.
“We need candidates who are willing to speak truth about the election, who are willing to push back,” she said during an interview at the Conservative Political Action Conference in February, where she also bragged that Facebook had removed an interview she had done with the former Trump adviser Stephen K. Bannon in which she asserted that the election had been stolen. “If you’re not willing to say what happened in 2020, then, gosh, you don’t deserve to be elected.”
Ms. Leavitt later accused Mr. Mowers of siding “with Joe Biden and the Democrats by refusing to stand for election integrity and support audits.” She has also said she would support Mr. Jordan for speaker rather than Mr. McCarthy, though she later said she would back Mr. McCarthy.
At a recent debate, when asked whether he would support impeaching President Biden, Mr. Mowers said he would want to have hearings to look into the issue. Ms. Leavitt said without qualification that she would support any impeachment charge against the president.
Each candidate has been savaging the other as a creature of Washington. Mr. Mowers’s campaign operates a “fake MAGA Karoline” website, which accuses her of having “never held a real job outside the swamp,” attending private school in Massachusetts and being registered to vote from the “penthouse” apartment where she lived in Washington before moving back to New Hampshire to run for office.
On a site operated by Ms. Leavitt’s campaign, titled “backdoor Matt,” the campaign refers to Mr. Mowers as a “Fauci foot soldier” for his role working in the administration for Dr. Deborah Birx, the former White House coronavirus coordinator. It also refers to him as a “big pharma bro” who worked as a lobbyist for a pharmaceutical company.
“Matt Mowers is the swamp,” the website proclaims, noting that he voted in two states — New Hampshire and New Jersey — in the 2016 Republican presidential primary.
The race has grown so close and so heated that it is drowning out New Hampshire’s competitive Senate race, with ads from both campaigns blanketing the 5 p.m. news.
A recent poll conducted by the University of New Hampshire Survey Center showed Mr. Mowers leading Ms. Leavitt by a razor-thin margin: 26 percent to 24 percent, barely more than the 2.2 percent margin of error, though 26 percent of likely voters said they remained undecided. A third Trump-aligned candidate, Gail Huff Brown — whose husband, the former Massachusetts senator Scott Brown, served as Mr. Trump’s ambassador to New Zealand — was trailing with 16 percent. Two other lesser-known candidates have gained little traction in the race.
Money has also poured into the contest, with several outside groups spending millions of dollars trying to defeat Ms. Leavitt, who some Republicans fear could be a weaker opponent against Mr. Pappas.
“Mowers probably has a slight advantage in running against Pappas, because he’s already done it,” said Thomas D. Rath, a former New Hampshire attorney general and longtime Republican strategist. “But she’s engaging because of her youth, her energy and her fierce competitiveness. The momentum is with her.”
Even top House Republicans are torn over the race, signaling lingering divisions in the party that could shape how it defines itself no matter who wins. For Mr. McCarthy, who is campaigning to be speaker, a victory by Mr. Mowers would add a reliable ally to his ranks. Ms. Leavitt would be a wild card more in the mold of Representative Marjorie Taylor Greene of Georgia and other hard-right lawmakers who have sometimes proved a thorn in Mr. McCarthy’s side.
A senior Republican strategist close to Mr. McCarthy said Mr. Mowers was one of several candidates who ran in 2020 whom the leader was supporting this election cycle, in part because he believed their name recognition and established networks of donors would position them for victories in the general election.
But Ms. Stefanik, who has styled herself in Mr. Trump’s image and has ambitions to rise in the party, is backing Ms. Leavitt, who previously worked as her communications director. She calls Ms. Leavitt “a rising star in the Republican Party who will carry the torch of conservative values for generations to come.”
The Congressional Leadership Fund, a super PAC aligned with Mr. McCarthy, has spent more than $1.3 million supporting Mr. Mowers. Another super PAC that supports moderate Republicans, Defending Main Street, has spent over $1.2 million and is running an ad that describes Ms. Leavitt as a “woke Gen-Z’er” and plays a Snapchat video she once posted where she uses crude language to refer to her viewers.
E-Pac, Ms. Stefanik’s outside group that supports conservative female candidates, has maxed out to Ms. Leavitt’s campaign, and Ms. Stefanik has served as an informal adviser to her former aide.
Ms. Leavitt has leaned into the attacks to paint herself as a victim. “I am officially the top target of DC’s money machine,” she posted on Twitter this week. “The Establishment knows I am the greatest threat to their handpick puppet Matt Mowers.”
Ms. Leavitt’s backers view the money elevating her opponent and the increasingly negative attacks against her as signs of fear from Mr. Mowers and Mr. McCarthy, who they say is trying to put together a compliant conference and views Ms. Leavitt as a maverick who would be difficult to control.
In order to sell himself as the Trumpier candidate, Mr. Mowers has advertised his 2020 endorsement from the former president on his campaign mailers, even though Mr. Trump has not made an endorsement in the current contest. (A top Trump aide said he was “still thinking about the race.”)
Despite the heated attacks and the stylistic differences, operatives with both campaigns admit there is little that distinguishes the candidates on policy. In their ads introducing themselves to voters, Ms. Leavitt and Mr. Mowers both come across as deeply angry about the state of the country under Mr. Biden’s leadership and pitch themselves as fighters who want to secure the border and stand in the way of Mr. Biden’s agenda. Both oppose abortion rights at the federal level, saying the issue should be left to states.
Their rivalry has given Democrats renewed hope of holding the seat. Collin Gately, a spokesman for Mr. Pappas, said the contest had given New Hampshire voters “a front-row seat to the MAGA show” that has prompted both candidates to “run to the right.”
“Their eventual nominee is getting weaker by minute while we’re building a bipartisan coalition to win in November,” Mr. Gately said.