In the 2022 cycle, the National Republican Senatorial Committee, under the chairmanship of Senator Rick Scott, took a largely hands-off approach to the primaries. Mr. McConnell lamented the “candidate quality” of those who had emerged from primaries, and several Republicans went on to lose key battlegrounds in November, including Don Bolduc in New Hampshire and Blake Masters in Arizona, both of whom party strategists had predicted would be weak nominees.
Mr. Daines has taken a different approach. He has endorsed Representative Jim Banks for an open Senate seat in Indiana and has courted other candidates, including David McCormick, the former hedge fund executive who lost a Senate primary in Pennsylvania last year, to run again.
Still, Senate Republicans are facing a gantlet of potential 2024 primaries, and the party leadership is worried that weak potential candidates could yet again hinder Republicans in November, including in Mr. Daines’s home state, Montana.
In West Virginia, for instance, national Republicans have wooed Gov. Jim Justice, a billionaire former governor, to run against Senator Joe Manchin III, a Democrat who faces a tough re-election fight in a state that Mr. Trump won overwhelmingly in 2020. Mr. Justice is expected to enter the race on Thursday, but Representative Alex X. Mooney, who won a fierce Republican primary in 2022 with Mr. Trump’s endorsement, has already entered the contest.
Other states that may feature thorny Republican primaries include Arizona, where the former television newscaster Kari Lake, who lost her 2022 bid for governor, may run for Senate in 2024, and Pennsylvania, where Doug Mastriano, who badly lost a 2022 governor’s race, is looking at a Senate run.
“The primary is ours to walk away with,” Mr. Mastriano said in an interview on Monday with the conservative radio host John Fredericks. “We have the base. We are the base.”
Mr. Mastriano is the type of nominee Mr. Daines is seeking to avoid. “His last race demonstrated he can’t win a general,” Mr. Daines said last month.
