John Hickenlooper, the former Colorado governor who ended his presidential campaign last week, announced Thursday that he would run for a United States Senate seat in his home state, instantly making him one of the Democrats’ best hopes in their quest to retake the chamber next year.
Mr. Hickenlooper was resistant to the idea of running for the Senate while he was still in the presidential race, telling reporters that he was “not cut out to be a senator.” But discussions about a bid grew serious in recent weeks as his campaign faded, senior aides abandoned his team and he failed to secure a spot in the next Democratic debate.
“I’ve always said Washington was a lousy place for a guy like me who wants to get things done,” Mr. Hickenlooper said in a video posted on his campaign website Thursday morning. “But this is no time to walk away from the table.”
Mr. Hickenlooper, who is also a former Denver mayor, brewpub owner and geologist, will seek to challenge Senator Cory Gardner in a contest that Democrats view as all but necessary to win if they have any hope of flipping the Senate in 2020.
While Mr. Hickenlooper’s laid-back style and moderate politics never caught on in the presidential race, he remains popular in Colorado, a battleground state. A recent poll showed Mr. Hickenlooper with more than a 50-point lead over the current leading Democrats in the race for the party’s nomination for the Senate seat; another poll showed him ahead of Mr. Gardner by 13 percentage points in a head-to-head matchup.
The advocacy group that commissioned one of the polls, 314 Action, hailed Mr. Hickenlooper’s decision on Thursday. “With Governor Hickenlooper in the race, we have a stronger chance to flip the Senate and take real action on climate change,” said Shaughnessy Naughton, the president of the group, which supports scientists running for office.
Mr. Gardner’s campaign dismissed concerns about a challenge from Mr. Hickenlooper on Thursday. “To us Governor Hickenlooper is just another liberal in the clown car,” said Casey Contres, Mr. Gardner’s campaign manager. “Whoever their party nominates will be wildly out of step with Colorado and we look forward to facing them in the general election.”
Mr. Hickenlooper’s Senate candidacy is a new illustration of how heavily Democrats are relying on Western states to build a majority in the chamber. Democrats captured two Republican-held Western Senate seats in 2018, in Arizona and Nevada, and they are aiming in 2020 to seize the other Arizona seat and the Colorado seat that Mr. Hickenlooper is now contesting.
The regional shift toward Democrats in these increasingly diverse and urban states has helped the party compensate, in part, for the ground it has lost across rural America and the Southern states where Democrats have suffered extinction-level losses in statewide elections.
Democrats will need to pick up at least three seats to take control of the Senate next year, but the party has struggled to convince some of its highest-profile names to run. Former Representative Beto O’Rourke of Texas and Gov. Steve Bullock of Montana have been urged by some members of their party to drop out of the presidential race and make Senate bids, but both have demurred.
Mr. Hickenlooper’s exit from the presidential contest may have presaged a new phase of the race, in which candidates who cannot make the debate stage will find it increasingly difficult to sustain their campaigns. On Wednesday, Gov. Jay Inslee of Washington, who also struggled to break through in the polls, said he was ending his bid for the Democratic nomination.
With Mr. Hickenlooper and Mr. Inslee out of the race, Mr. Bullock is now the only Democratic governor, current or former, seeking the presidency.
Alexander Burns contributed reporting.