Former Colorado governor John Hickenlooper, who dropped out of the Democratic presidential contest last week, has launched a bid for a U.S. Senate seat with the aim of ousting Cory Gardner, regarded as one of the most vulnerable Senate Republicans in 2020.

In an announcement video posted Wednesday night, Hickenlooper proclaims himself a “straight shooter” as he’s seen playing pool in a Denver brewpub he co-founded.

“I’ve always said Washington was a lousy place for a guy like me who wants to get things done, but this is no time to walk away from the table,” the former two-term governor says. “I know changing Washington is hard, but I want to give it a shot. I’m not done fighting for the people of Colorado.”

In the video, Hickenlooper pledges to work on several issues, including protecting the health insurance of people with preexisting conditions, lowering prescription drug prices, combating climate change and protecting public lands.

Hickenlooper had been under pressure from national and state Democrats to abandon his presidential ambitions to challenge Gardner in what the party views as a prime pickup opportunity next year in the Senate.

Gardner narrowly defeated Democratic incumbent Mark Udall in Colorado’s 2014 Senate race. After the 2018 midterm elections, he became the only Republican holding statewide elected office in Colorado.

Hickenlooper’s announcement upends a crowded Democratic primary field in Colorado. A recent poll conducted by Garin-Hart-Yang Research Group for an unnamed national organization showed Hickenlooper with a massive lead in a potential Democratic Senate primary, favored by 61 percent of likely voters. The nearest rival came in at 10 percent.

The National Republican Senatorial Committee pointed Thursday to several previous comments by Hickenlooper about his aversion to serving the Senate, including a statement that “it just doesn’t attract me.”

“John Hickenlooper is desperate to redeem himself after flopping on the national stage, but we think he said it best just a few months ago: he is ‘not cut out’ for the Senate,” NRSC spokeswoman Joanna Rodriguez said in a statement. “This crowded Senate field has been in a race to the left and Hickenlooper’s quixotic presidential bid did not do him any favors in proving he can compete in any race in 2020.”

Hickenlooper, who finished his tenure as governor at the beginning of the year, had struggled to translate his popularity in Colorado to the presidential race. In a field of more than 20 candidates, Hickenlooper remained stuck near the bottom of the pack, struggling to top 1 percent in most national polls.

He participated in the first two debates, in Miami and Detroit, but did not meet the qualifications established by the Democratic National Committee for the third debate, which will be held in Houston in mid-September.

In a video released at the end of his presidential bid, Hickenlooper pledged to give the Senate race “some serious thought.”

Hickenlooper governed as a business-friendly Democrat in Colorado while advocating some progressive policies. He positioned himself in the nomination contest as a pragmatic moderate.

In his Senate announcement video, Hickenlooper takes aim not only at Gardner, but also at Senate Majority Leader Mitch McConnell (R-Ky.) and President Trump.

“I don’t think Cory Gardner understands that the games he’s playing with Donald Trump and Mitch McConnell are hurting the people of Colorado,” Hickenlooper says. “We ought to be working together to move this country forward, and stop the political nonsense.”

Dan Balz and Felicia Sonmez contributed to this report.