A progressive, mustachioed Bernie Sanders supporter has shot to fame after announcing a challenge to Republican house speaker Paul Ryan.

Democrat Randy Bryce, who goes by @IronStache on Twitter, is an ironworker, union organiser and veteran who launched his bid for Wisconsin’s first congressional district on Monday.

Since then, his evocative campaign advert, which shows a denim- and boot-clad Bryce discussing healthcare with his mother and engaging in various forms of metalwork, has been watched more than 330,000 times, and the 52-year-old has attracted a level of internet acclaim rarely seen among political candidates.

“I knew that we would have a successful launch,” Bryce told the Guardian on Thursday. “But I honestly did not have any kind of idea it would blow up as big as it has.”

His popularity has been fuelled by his progressive agenda – he is in favor of a single-payer healthcare system and spoke at a Sanders event during the Democratic primaries – but appears to have also been aided by his all-American appearance and luxuriant moustache.

Bryce’s image prompted one Twitter user to suggest Bryce was “genetically engineered from Bruce Springsteen songs”, while several people compared the Democrat to the Parks and Recreation character Ron Swanson.

Whereas Swanson is a proud libertarian, however, Bryce describes himself as a progressive, and he has already won the support of People for Bernie, a group which formed during Sanders’ campaign and is now devoted to electing leftwing candidates into office.

Bryce’s advert shows him sitting with his mother, who has multiple sclerosis, as she explains how she has to take 20 tablets a day, at a cost of thousands of dollars. His mother has health insurance, but the risk of Republicans repealing Obamacare, and potentially stripping 23 million people of their health coverage, is a central concern of Bryce’s campaign.

“I shouldn’t have to say, ‘Luckily she has insurance.’ It should be something everyone has,” Bryce said. “Single payer works in other countries.”

Bryce served in the US army and was posted to Honduras before returning to his home in Caledonia, in south-eastern Wisconsin. He has since spent two decades as an ironworker, and aims to contrast that with Ryan’s record.

“I’ve been doing this for 20 years. And that’s about the same time that Paul Ryan has been in Congress. And I mean, I’m driving around and I’m pointing out to my son: ‘Look, daddy built that, daddy worked on that.’

“And I’m proud of helping build things in the last 20 years. And then I look at what Paul Ryan has done and he’s done nothing.”

Wisconsin’s first congressional district is seen as something of a bellwether, the electorate having gone for George W Bush in 2004, Barack Obama in 2008, and Donald Trump in 2016 (although Mitt Romney carried the district in 2012).

But Ryan, currently the most senior Republican in Congress, has rarely been threatened since he was first elected in 1999. In 2016, the House speaker won 65% of the vote and neither the Cook Political Report nor Ballotpedia rate the first district as likely to swing to the Democrats.

Bryce’s previous runs for office also do not bode well. According to the Milwaukee Journal Sentinel, he lost races for Wisconsin’s state legislature in both 2012 and 2014, and in a run for Racine County board of education in 2013.

Still, this time Bryce is hoping to benefit from the progressive wave that began under Bernie Sanders, and has seen leftwing Democrats outperform expectations already in 2017. His progressivism and stance on healthcare is also likely to attract support from activist groups eager to elect populist candidates to office.

In the meantime, Bryce said his @IronStache Twitter handle – an unconventional tag for a potential congressman – is going nowhere.

“When talking about running for Congress I decided I’m not going to make a different ‘RandyBryceforCongress’ thing, because I’m not going to pretend to be something I’m not,” Bryce said.

“I’m a working guy and what you see is what you get. I’m going to be me, and I think that’s what we need in our representation.”