Gov. Steve Bullock of Montana is poised to reverse himself and run for the Senate, according to three Democratic officials, a decision that would hand the party a coveted recruit who could help reclaim a majority in the chamber.
After months of insisting he would not challenge Senator Steve Daines, Mr. Bullock, who ran for president last year, has told Democrats in the last week he is now inclined to run in what would immediately become one of the marquee Senate races of 2020. Mr. Bullock has only a few days to finalize his decision: The filing deadline to run in Montana is Monday.
In an email on Tuesday, Mr. Bullock, 53, declined to say whether he would run. But Matt McKenna, an adviser to Mr. Bullock who has long argued that the governor would not run for the Senate, on Wednesday would say only, “I don’t have anything for you.”
The Democratic officials spoke on the condition of anonymity to discuss internal deliberations.
Senate Democrats are chiefly on the offensive this year, and have high hopes to defeat incumbent Republicans in Arizona, Colorado, Maine and North Carolina, where on Tuesday their preferred candidate captured the nomination. But with Republicans holding a 53-seat majority, and favored to defeat Senator Doug Jones of Alabama, it has not been clear which state could offer Democrats the fifth seat they would need to win a clear majority.
For months, even when he was still a presidential candidate, Mr. Bullock has faced questions about whether he would take on Mr. Daines. And when he dropped out of the presidential race in December — after a spirited but underfunded campaign — he again said that he would not run for the Senate.
But Mr. Bullock, who is barred by term limits from running for re-election this year, has faced one of the most sustained lobbying campaigns of any would-be Senate candidate — a reflection both of his potential as a candidate and how badly Democrats need to put another seat in play.
Senator Chuck Schumer of New York, the minority leader, flew to visit him in Montana last month. And when Mr. Bullock was in Washington last month for the meeting of the National Governors Association, he also met with former President Barack Obama, as was reported by Politico.
At a fund-raising reception in New York City for Senate candidates last month, Mr. Schumer revealed that he was traveling to Montana and projected confidence that Mr. Bullock would agree to run, according to an attendee.
More quietly, a handful of union officials have reached out to Mr. Bullock to assure him he would have all the resources he needs in a state that still retains a strong labor tradition, according to one of the party officials, who was familiar with the conversations.
“I’m hopeful,” said Randi Weingarten, the president of the American Federation of Teachers, the powerful educators’ union, about the prospect of the governor entering the race.
What may have proved most decisive for Mr. Bullock, however, is that his family is supportive of his candidacy, according to the officials familiar with the discussions. He has long been reluctant to commute to Washington because of the toll he feared it would take on his family.
While his party has been avidly pursuing him, Mr. Bullock is not the only Democrat interested in the race. A handful of candidates are already running, including Mayor Wilmot Collins of Helena and Cora Neumann, an economic development executive who has already raised over $600,000 for her bid.
Mr. Bullock, who was Montana’s attorney general before being elected twice as governor, ran for the Democratic presidential nomination last year calling for an overhaul of the country’s campaign finance laws and urging Democrats to pay more attention to rural areas and the West.
But after running as a defender of gun rights in his earlier campaigns, Mr. Bullock said during his White House bid that he supported banning the sale of assault weapons, limiting the sizes of ammunition magazines and enforcing a waiting period to purchase firearms that provided “sufficient time for a full background check of the purchaser,” as he put it in a New York Times survey. Mr. Daines and Republicans are sure to attack Mr. Bullock on those issues, even as some restrictions on firearms have grown more palatable in Montana.
Mr. Daines, a first-term conservative, has forged a close relationship with President Trump, who has repeatedly tweeted his support for the incumbent.
Mr. Trump again hailed Mr. Daines on Wednesday: “Whoever the Democrat nominee may be, please understand that I will be working hard with Steve all the way,” he wrote.
Mr. Trump is likely to carry Montana in the presidential election, just as he did in 2016, but Mr. Bullock could prove a formidable contender in the Senate race. That would particularly be the case if Democrats enjoy the sort of enthusiasm that helped propel Montana’s other senator, Jon Tester, to re-election in 2018.
The larger question may be whether a Democrat running in a red state — and one who mounted a bid to unseat Mr. Trump — can prevail in a presidential election year and at a moment of such extreme polarization.
Twice elected governor while Democratic presidential candidates were being routed in Montana, Mr. Bullock largely governed as a pragmatist, expanding Medicaid in the state with bipartisan support.
He sought to carry his résumé to Iowa in the presidential race, but drew little support and even less money in a race dominated by flashier and better-known Democrats.
Should he enter the Senate race, money would be the least of his challenges: A Daines-versus-Bullock contest, with control of the Senate possibly at stake, would very likely be the most expensive campaign in Montana history.
Catie Edmondson contributed reporting.