Randy Bryce, an Army veteran and ironworker, has announced that he will challenge Speaker of the House Paul Ryan, R-Wisconsin, in 2018.

Bryce, a Democrat who is active on Twitter under the handle @IronStache, has already run for office twice before, losing state House races in 2012 and 2014. But his first campaign ad quickly went viral, and is already turning heads in what could prove to be a major contest in next year's midterms.

Wow—This ad by union ironworker Randy Bryce, who is challenging Paul Ryan is seriously powerful & moving @IronStache https://t.co/Yso8SxIvm6 — Steven Greenhouse (@greenhousenyt) June 21, 2017

President Trump won Wisconsin's 1st Congressional District, which Ryan represents, by 10 points last November. And it's unusual, although not unprecedented, for sitting House Speaker's to lose reelection. The last time that happened was 1994, when Speaker Tom Foley, D-Washington, lost his seat in the "Republican Revolution" that returned the chamber to GOP control after decades in Democratic hands.

Ryan has represented the district since 1999, and became Speaker in 2015. Since then, he has always been reelected with more than 50 percent of the vote. In 2016, he won 65 percent of the vote.

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Bryce, however, insists that Ryan is vulnerable, and is expected to campaign with a message centered on health care. "It's not the same Paul Ryan that initially ran," Bryce told NPR over the weekend. "He - I mean, even now he'll come across as a nice guy, but it's been over 600 days since the man has had any kind of public listening session in the district."

Bryce supported Sen. Bernie Sanders, D-Vermont, in last year's contentious Democratic presidential primary. His run could indicate whether Democrats will be successful in adopting a more progressive message, particularly in working class districts that went for Mr. Trump in the last general election.

Despite Mr. Trump's success in the district, and though it does tilt Republican, it only narrowly went for Republican presidential nominee Mitt Romney in 2012, and was won by Democratic presidential nominee Barack Obama in 2008. And given Ryan's role in leading a deeply unpopular Congress, which has struggled to deliver on its legislative goals since Mr. Trump took office, there is perhaps a chance that Bryce could make history by flipping the district.

"I'm running being me," Bryce told NPR. "I'm not trying to be anything. I'm not a politician. I'm a working guy that has - you know, lives in a neighborhood of working people. And it's standing up and it's listening. The big thing right now is working people want to be heard."