On Feb. 17, 2016, shortly after the death of Supreme Court Justice Antonin Scalia, Chris McDaniel turned on Facebook Live and began taking questions. One dealt with Mississippi’s looming presidential primary, and whether Trump could be stopped. McDaniel, who had endorsed Sen. Ted Cruz (R-Tex.) for president, shared his worry: Trump’s small, strong base could get him through the primary, even if he wasn’t a true conservative.

“Trump endorsed me in 2014,” McDaniel said. “Trump is not a constitutional conservative. He’s just not. I wish that were not the case, because I like his ability to speak his mind … but I don’t hate the establishment more than I love conservatism.”

McDaniel’s answer, which has been promoted by his enemies on social media for months, is now at the center of an attack ad in the state’s November special election. The campaign of Sen. Cindy Hyde-Smith (R-Miss.), who was appointed to the seat in the spring, repurposed the video to inform voters of “what Chris McDaniel is saying about Donald Trump.”

McDaniel, like nearly all conservatives, has completely shifted his opinion of Trump since 2016. But like several other candidates in this cycle, his worries about Trump — that he had no reliable record on key conservative issues — has been weaponized against him by more center-right Republicans who want to stop insurgent candidates. Since the start of 2017, in primaries that pit several conservatives against each other, many ads move away from issues or votes to focus on candidates’ loyalty to the GOP — and to Trump, in particular.

The Hyde-Smith ad resembles the spots that Republicans ran to stop Rep. Mo Brooks (R-Ala.), another Cruz endorser, in his 2017 primary against then-Sen. Luther Strange. During the 2016 primary, Brooks went on TV and radio shows to fret that Trump was not trustworthy as a conservative, was alienating voters, and was likely throwing away the election.

Strange, who was Alabama’s attorney general in 2016, was on the record backing Trump. So was Hyde-Smith — and so was McDaniel, who like Cruz decided to support Trump after he won the party’s nomination.

But for weeks, McDaniel had been busy attacking Hyde-Smith over her own political past. Until December 2010, Hyde-Smith was a Democrat. In 2008, she voted in the state’s Democratic primary for president; she has not said whom she supported.

Hyde-Smith is not the only convert to the GOP who’s being attacked on her past. In Wisconsin, a super PAC backing state Sen. Leah Vukmir is beginning to run a spot that attacks primary opponent Kevin Nicholson for comments he made in 2000, as a leader of College Democrats. Next to images of Hillary Clinton — who addressed that year’s DNC as a candidate for U.S. Senate — the ad plays back Nicholson’s quotes in favor of “a woman’s right to choose.” Nicholson’s shift to the GOP has been central to his campaign narrative; here, it’s central to the case against him.

Another Alabama race has seen both kinds of loyalty attacks flying across the airwaves. In the 2nd Congressional District, where Rep. Martha Roby (R-Ala.) faces an Aug. 17 runoff, former U.S. congressman Bobby Bright has attacked largely the incumbent for distancing herself from Trump during the “Access Hollywood” tape scandal. “Martha Roby said she supports the president now,” says a narrator in his most-aired ad, “but Roby turned her back on the president when he needed her most.” The evidence: a post-“Access Hollywood” news conference at which Roby urged Trump to quit the race and let Mike Pence lead the Republican ticket.

Bright, however, is in a singularly weak position for attacking Roby. He served one term in Congress, from 2009 to 2011 — and backed Nancy Pelosi for speaker of the House. Even though Bright broke with Pelosi on the party’s major priorities, including the Affordable Care Act, ads by Roby and allies, like the U.S. Chamber of Commerce, have branded him a Pelosi Democrat trying to pull one over on voters.

Trump has endorsed Roby for reelection. He has made no endorsement in the Mississippi race.