Americans for Prosperity, the conservative advocacy group backed by the Koch brothers, is launching an aggressive six-figure advertising campaign to defeat Rep. Renee Ellmers, who faces two challengers in the North Carolina GOP primary in June.

It marks the first time the group is spending big to defeat a Republican incumbent in a primary race at the federal level, and it could prove troublesome for Ellmers (R-N.C.), who was elected in the 2010 tea party takeover of the House.

In one YouTube ad posted Thursday, a narrator says Ellmers “became part of the Washington problem,” and encourages North Carolinians to vote against her. The same ad praises one of Ellmers’s challengers, Rep. George Holding (R-N.C.).

Ellmers, Holding and Greg Brannon — who ran twice for the North Carolina Senate seat — are facing off on June 7 in the state’s newly redrawn 2nd Congressional district.

“It’s the quintessential example of someone who promised one thing and went to Washington and changed,” said AFP spokesman Levi Russell. “In Renee Ellmer’s case, it was telling voters she was going to represent limited government and then [she] voted for higher spending and corporate welfare.”

The ads will run online, in addition to mailers sent out in the district and grassroots efforts by AFP staff in North Carolina who will knock on doors urging voters not to support Ellmers. It is unusual for AFP, which typically targets Democrats in attack ads, to engage so aggressively in a Republican primary. But the move is not entirely surprising.

Ellmers has been cast by conservatives as an ally of the Republican establishment she vowed to fight against. They have criticized her for, among other things, her support for reauthorizing the Export-Import Bank, rejecting a bill meant to push back against President Obama’s immigration executive action, and her involvement in delaying a measure that would have imposed a ban on abortions after the 20th week of pregnancy. Russell also criticized Ellmers’s support for the 2014 farm bill and 2013 budget deal.

The Club for Growth, another conservative outside group, is also opposing Ellmers’s reelection.

AFP is also considering weighing in on the North Carolina Senate race as well, which pits Sen. Richard Burr (R-N.C.) against Democratic challenger Deborah Ross.

Even though AFP is not formally endorsing Holding, the ad does frame him as a favorable alternative to Ellmers.

“I am pleased and I think it’ll be helpful,” said Carter Wrenn, an adviser for the Holding campaign.

Ellmers’s campaign shot back at AFP and Holding, unveiling a radio ad Thursday accusing the congressman of lavish spending on a congressional trip to Jordan in 2015.

“If AFP, like Renee Ellmers, wants the government to stop spending so much money, they should refrain from supporting candidates like George Holding, who spends tens of thousands of dollars of our tax dollars to buy himself first-class tickets to foreign countries,” said Patrick Sebastian, an adviser for Ellmers’s campaign.

Correction: An earlier version of this post misspelled the name of AFP’s Levi Russell.