(WASHINGTON) — Just 10 days into his congressional career, Michigan Rep. Peter Meijer broke with his party and voted with nine other Republicans and every Democrat in the House to impeach President Donald Trump over the Capitol riot.

Now, just days before his primary, Meijer is under pressure from a major Democratic group, which is spending $500,000 to spotlight John Gibbs, his pro-Trump, election-denying opponent.

Airing in Western Michigan this week, the 30-second ad from the Democratic Congressional Campaign Committee (DCCC), House Democrats’ campaign wing, describes Gibbs, who worked in the Trump administration, as “too conservative” for the region and Trump’s “hand-picked” candidate.

While the DCCC’s messaging is negative, the ad pulls focus from Meijer and underscores Gibbs’ conservative credentials shortly before voters have their say.

At a time when Democrats are warning voters that election-denying Republicans pose an existential threat to democracy, the party’s role in a messy GOP primary has left multiple Democratic lawmakers angry and frustrated.

“There’s always a danger of unintended consequences, and I certainly would have taken a different approach,” Colorado Rep. Jason Crow told ABC News on Wednesday. “We should play our game on our terms, and I don’t think approaches like that are usually productive.”

“I thought it was a strange choice, and I called [the DCCC] and let them know,” Michigan Rep. Elisa Slotkin told ABC News.

Rep. Fred Upton, R-Mich., a retiring moderate who also voted to impeach Trump, called the Democratic strategy “outrageous” and pointed to Meijer’s votes across party lines on impeachment and to protect same-sex marriage rights.

“Peter’s been a strong independent voice, and he’s put the country first on a number of issues,” Upton told ABC News. “He’s not a rubber stamp.”

New York Rep. Sean Patrick Maloney, the chairman of the DCCC, defended the party’s efforts on Wednesday. He argued that the ad was “telling the truth about John Gibbs being a dangerous extremist” and that Democratic candidate Hillary Scholten — who will face either Gibbs or Meijer — would “put people over politics” if elected to serve in the House.

In a brief interview in Washington on Wednesday, Meijer accused Democrats of putting “party interest” first.

“Everything they’re saying in the Jan. 6 committee, everything about how my party is a threat to democracy — and they are investing a half-million dollars to elevate and boost exactly the same thing that they’re railing against?” he said.

“It’s pretty galling in the hypocrisy of it all. And just shameless given their high-minded rhetoric about how they are the party of democracy. Spare me that bull—,” Meijer said.

Rep. Adam Kinzinger, R-Ill., a retiring member of the House Jan. 6 committee, called the strategy “disgusting” in an interview with CNN, warning that it would help “election deniers win.”

Gibbs, who served in the Department of Housing and Urban Development under Trump, was unsuccessfully nominated to lead the Office of Personnel Management but faced criticism in the Senate over past comments and tweets, including speaking dismissively of Islam and promoting a conspiracy theory involving Democrats. (Gibbs said at the time that “I don’t really see anything to apologize for. I was a commentator.” At his confirmation hearing, he insisted, “In my service in the government … I’ve always treated people fairly.”)

Democrats aren’t just focusing on the right-wing candidate in Meijer’s race. The party has tried to influence GOP primaries across the country — where nominating more conservative options could create more favorable matchups in November and maintain their slim House and Senate majorities.

In California, an outside political group affiliated with House Democratic leaders tried spotlighting a pro-Trump Republican running against Rep. David Valadao, another one of the 10 GOP members who voted to impeach Trump. (Valadao survived his primary two weeks ago and advanced to the general election through California’s top-two system.)

In Colorado, the Democratic leadership-aligned Senate Majority PAC spent millions ahead of the primary last month to portray Joe O’Dea, a Republican seeking to unseat Democratic Sen. Michael Bennet, as a moderate compared to the more conservative Ron Hanks — which was ultimately unsuccessful. O’Dea said Democrats were “propping up Ron Hanks in a desperate attempt to save” Bennet in November.

And Democrats in Pennsylvania, ahead of the state’s GOP primary in early June, elevated Doug Mastriano, who was linked to Trump’s effort to challenge the 2020 election and the Capitol attack. (Mastriano was at the Capitol that day but insists he left because of the violence.) He will face Democratic state Attorney General Josh Shapiro in November.

Rep. Dean Phillips, D-Minn., tweeted this week that he was “disgusted” that the DCCC has been using its funds — including membership dues paid by lawmakers — to “boost Trump-endorsed candidates, particularly the far-right opponent of one of the most honorable Republicans in Congress.”

Helen Kalla, a spokesperson for the DCCC, told ABC News the group was “laser focused on holding the House majority, which we will accomplish by fighting for every competitive seat.”

“[Minority Leader] Kevin McCarthy is an anti-choice insurrectionist coddler and conspiracy enabler, and we will do what it takes to keep the speaker’s gavel out of his hands,” Kalla said.

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