WASHINGTON — If Democrats care as much about electability in 2020 as they tell pollsters they do, then Steve Bullock has a case to make, even with 21 other candidates in the race.

The Montana governor declared his bid for the Democratic presidential nomination in a video Tuesday, highlighting the fact that he's the only candidate in the race to have won in a red state.

"We need to defeat Donald Trump in 2020 and defeat the corrupt system that lets campaign money drown out the people's voice, so we can finally make good on the promise of a fair shot for everyone," Bullock said in a statement.

Montana Governor Steve Bullock campaigns at a gathering of Democrats in Livingston on July 2, 2016. William Campbell / Corbis via Getty Images file

Bullock will speak later in the day at a high school in Helena, where his daughter is a student, and then head to Iowa later this week.

He entered the race so late because had to wait for Montana's legislature, which meets for only a few months every two years, to conclude its work on some 300 bills.

But the timing is hardly his only challenge, though.

Bullock is hardly a household name, even in households of political junkies. At a gathering of progressive activists last summer in New Orleans, Bullock had to introduce himself and moderate a panel on Net Neutrality in a small room, while better-known contenders like Sen. Elizabeth Warren, D-Mass., spoke to thousands in the main hall.

But allies of the easygoing 53-year-old lawyer, known for wearing cowboy boots and jeans as much as suits, think he could be the next candidate to have a breakout moment, following former Rep. Beto O'Rourke and Mayor Pete Buttigieg of South Bend, Indiana.

Core to Bullock's case is that he won Montana twice, including his reelection in 2016 on the same night as Donald Trump won it in a landslide.

He did it while sticking to core Democratic values on everything from abortion to climate change to guns. He also managed to pass progressive legislation through the Republican-controlled state legislature, including two Medicaid expansions and some of the strictest campaign finance laws in the country.

And he used executive authority to protect LBGT state employees from discrimination and to make his the first state in the country to enforce Net Neutrality after the FCC rolled back prior rules.

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All that has attracted some well-known allies, like former Hillary Clinton communications director Jennifer Palmieri, who has been an informal advisor, but says she will not be part of the campaign. Iowa Attorney General Tom Miller, the only Democrat who consistently wins statewide in the increasingly red state, is supportive, too.

Still, Bullock's team is well aware he's a long shot, with little money, name-recognition and a late start. Even making the first debate on June 26-27, hosted by NBC, will be a big challenge.

And his presidential ambitions have frustrated some Democrats who say he'd be far more valuable to the party by running for the Senate next year against Republican Steve Daines than by adding his name to the already long list of presidential contenders.

But Bullock has rebuffed those pleas and instead spent part of the past two years quietly laying the groundwork for White House run, traveling to early primary and caucus states and meeting with national reporters and others to argue Democrats need someone who can win in rural areas.

"Democrats need to be showing up. Large swaths of the country have been written off," he told NBC News on the sidelines of a National Governors Association meeting in Providence, Rhode Island, in 2017. "And that's no way to win elections. But more importantly, that's no way to govern."