When J.R. Majewski emerged as the surprise winner of a Republican House primary election on Tuesday in northern Ohio, Democrats supporting the longtime incumbent congresswoman in the district, Marcy Kaptur, celebrated.
That was because Mr. Majewski had beaten out two lower-key Republicans for the nomination, both of whom Democrats worried could have posed serious problems for Ms. Kaptur in the conservative-leaning Ninth Congressional District in a challenging election year for her party.
Mr. Majewski is anything but low key.
A hulking Air Force veteran who works in the nuclear security field, he first gained attention in Ohio by turning his lawn into a 19,000-square-foot “Trump 2020” sign.
During his campaign, he ran one ad showing him carrying an assault-style rifle in which he says, “I’m willing to do whatever it takes to return this country back to its former glory,” adding, “If I’ve got to kick down doors, well, that’s just what patriots do.”
He also posted a “Let’s Go Brandon” music video on his website in which he raps a verse, warning, “Just try to put a mask on me, you’ll see red, white and blue.”
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Mr. Majewski has a shot at winning in November: After the recent redistricting process, Ohio’s Ninth District went from being strongly Democratic to leaning Republican.
But as his political profile has risen, he has expressed several conspiratorial and fringe views.
In addition to advancing the lie that the 2020 election was stolen — now a common belief among Republicans — and floating doubts that the Capitol riot was driven by Trump supporters, he has expressed sympathy for believers of the QAnon conspiracy theory movement. He said last year that one of their false claims about a prominent Democrat being a pedophile was “plausible.”
Mr. Majewski, who did not respond to requests for comment, told a right-wing radio host in January that he had gone to Washington on the day of the Capitol riot, but had not participated in any violence.
“I went to Washington, D.C., on Jan. 6 and I’m proud of it,” he said. “I didn’t do anything illegal. Unfortunately, there were some that did.”
He added, invoking a baseless theory that the federal government had provoked the violence, “But, you know, we all know that a lot of that was driven by the F.B.I. and it was a stage show.”
Mr. Majewski has also made multiple appearances on a podcast and Twitch livestream belonging to a man who goes by Zak Paine, or Redpill78, who pushes the sprawling QAnon conspiracy theory and has talked about his belief that people are killing children to “harvest” a chemical compound from them.
Mr. Paine was barred from Twitch, the Amazon-owned livestreaming site, this year under the site’s new misinformation policy, but before that he hosted Mr. Majewski and had asked his audience to donate to the candidate’s campaign.
On the streams, the two men vape, talk about Mr. Majewski’s campaign goals and take calls from Mr. Paine’s listeners.
“He is exactly the type of person that we need to get in Washington, D.C., so that we can supplant these evil cabal criminal actors and actually run our own country,” Mr. Paine said on one stream.
Mr. Majewski has denied being a believer in QAnon, which claims, among other outlandish things, that top Democrats and other government officials are part of a cabal of Satan-worshiping pedophiles.
“I’ve never read any QAnon drop — what they call the ‘Q-Drop,’” he told The Toledo Blade last year.
In an interview in September on a far-right podcast, Mr. Majewski was asked about QAnon. He said he had been called a QAnon adherent, but he rejected that characterization.
“God bless the folks that believe in the fact that they think that the Democrats are out killing babies and drinking blood and they have underground tunnels in Alaska and there’s earthquakes in Antarctica,” he said.
“That’s fine, if you want to believe it, that’s fine,” he said. “I’m never going to tell you anything otherwise. But if you ask me what my opinion is, I don’t think that happens.”
When the podcast host asked Mr. Majewski if he thought John Podesta, a former top aide to Hillary Clinton, “is a pedophile,” he replied, “I think there’s, again, a lot of information out there that’s compelling that, you know, is plausible that this guy, you know, is a pedophile.”
Mr. Podesta has dismissed QAnon believers’ attempts to connect him to their wild theories.
“It’s certainly no fun,” he told CNN last year. He went on, “There’s nothing, I think, to do other than to continue to fight back on the lies, and to really take seriously the issues around domestic violent extremism which we saw play out in the Capitol on Jan. 6.”