Republican Rep. Steve King, who is frequently criticized as aligned with the themes of white nationalism, is in the midst of a surprisingly tense reelection race in Iowa.

At least one poll has shown his Democratic challenger, J.D. Scholten, within striking distance, although FiveThirtyEight still gives King a nearly 83 percent chance of winning.

And growing attention to King’s affiliation with far-right groups and figures, including a Nazi sympathizer, has culminated with the possible beginnings of a donor boycott. A handful of corporations, including Intel and the dairy company Land O’Lakes, have announced that they will no longer support King financially. Even the Republican Party issued a sharp rebuke of King that stopped just short of saying he promoted white supremacy.

The scrutiny built toward a confrontation Thursday after King was harshly questioned about whether his racially tinged views on immigration shared any similarities with those of Robert Bowers. Bowers is the Pittsburgh synagogue shooting suspect who in social media posts reportedly said “invaders” were responsible for his “people” being “slaughtered.”

Video of the confrontation between King and his questioner circulated widely after being captured by the political blog, Iowa Starting Line.

A questioner in the room read statements from Bowers and King, then said he thought the two shared ideology regarding immigration.

“No, don’t you do that,” King said, cutting the man off. “Do not associate me with that shooter. I knew you were an ambusher when you walked in the room. But there’s no basis for that.”

The man — identified by the Des Moines Register as Kaleb Van Fosson of Ames, Iowa — continued trying to ask a question about what distinguishes King’s ideology. But the congressman cut him off.

“You’re done. You crossed the line. It’s not tolerable to accuse me to be associated with a guy that shot 11 people in Pittsburgh,” King said. “This is over, if you don’t stop talking.”

Van Fosson continued to press King, who interjected one final time.

“Sir, stop it!” King said, his voice cracking. He then asked security to remove Van Fosson from the room.

The Register reported that Van Fosson is a member of Iowa Citizens for Community Improvement, a group that protested outside the event. (On Thursday, Van Fosson shared video on Twitter that showed him attempting to talk to King at a different campaign event.)

King spokesman John Kennedy said that Iowans were calling in after seeing video of the confrontation to say they agreed with the congressman.

In an email to The Washington Post, Kennedy lambasted “Leftist Media Lies,” though he did not respond when asked to give specific examples.

King himself also mentioned “Leftist Media Lies” as he took to Twitter to share Iowa Starting Line’s video of the exchange.

King has come under fire in recent days after The Washington Post reported that he met with a far-right party with historical Nazi ties in Austria while on a trip to Europe that had been financed by a Holocaust memorial group.

At the forum in Iowa on Thursday, King defended the Austrian political group, saying that the party had purged former Nazis more than 50 years ago, except one with “a little youthful affiliation.” The party is now led by Heinz-Christian Strache, who was active in neo-Nazi circles as a youth.

King spoke about touring Holocaust sites in Poland before he flew to Vienna, an experience he said was moving.

His past statements — King has assailed immigrants, retweeted a Nazi sympathizer and said, “We can’t restore our civilization with somebody else’s babies,” in what many interpreted as an echo of the language of white nationalists — have drawn more scrutiny since the shooting massacre at a Pittsburgh synagogue.

Last month, King’s decision to endorse Faith Goldy also drew uproar. Goldy is a white nationalist candidate for Toronto mayor who appeared on a neo-Nazi podcast around the Charlottesville rally and later publicly recited a white supremacist slogan.

King blamed The Post for the attention, saying at the forum on Thursday that “the entire fiasco that you’ve seen here in the state for the last three days” was based on the report last week about the Austria trip.

King’s relationship with Sen. Ted Cruz (R-Tex.) — King was co-chair of Cruz’s presidential campaign in Iowa — has also come under question as the senator faces a tight reelection race in one of the country’s most racially diverse states. Cruz called King on Wednesday to express his support, even as donors and other party officials have moved away, Bloomberg News reported.

Mike DeBonis contributed to this report.

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