Fox News prime-time stars Tucker Carlson and Sean Hannity are locked in a rare head-to-head political showdown in Arizona, with each host publicly supporting a different Republican Senate candidate in the campaign to determine the party’s nominee against Sen. Mark Kelly. 

Carlson has rallied behind Blake Masters, the 35-year-old protege of fascist tech billionaire Peter Thiel and the former head of Thiel’s venture capital fund and foundation, while Hannity is backing the state’s Attorney General Mark Brnovich, a regular guest with a more traditional background as a former federal prosecutor, JAG officer in the U.S. Army National Guard, and director of a right-wing think-tank. 

The August 2 primary will test which host reigns as the chief kingmaker on the network that is synonymous with the GOP, potentially setting the stage for the presidential primaries in 2024. Hannity’s support was crucial in helping Donald Trump become the Republican nominee in 2016 — but Carlson, whom some GOP insiders reportedly consider a more potent force, didn’t have a prime-time show at the time.

With their endorsements, each Fox host stressed what the candidate meant for the future of the GOP. “The Republican Party is getting better, much better,” Carlson said in highlighting the “good news” of Masters’ run. Hannity, meanwhile, said in making his pitch for Brnovich, “I only support people that I personally know to be solid, America First, Make America Great Again, Save America, Reagan-Trump conservatives.” 

Each host has showered his chosen candidate with opportunities to sell himself to Fox viewers – beginning, in both cases, with interviews the very day the campaign launched. Masters has appeared on Tucker Carlson Tonight at least seven times since announcing his own run in July 2020, while Brnovich has gone on Hannity at least 23 times since he started his campaign the previous month, according to Media Matters' database of weekday cable news appearances. Those bookings are exclusive — neither host has interviewed or criticized the other candidate. Hannity has also hosted Brnovich as a candidate at least 14 times on his nationally syndicated radio show.

Hannity and Carlson have each helped deliver victories to their chosen candidates in high-profile GOP primaries this cycle, but they have avoided direct conflict with one another outside of the Arizona race. Hannity stayed out of the competitive Ohio Senate primary, in which Carlson endorsed Thiel-backed J.D. Vance. And Carlson ignored the Senate primaries in Georgia and Pennsylvania, where Hannity got behind former NFL player Herschel Walker and Dr. Mehmet Oz. Notably, in the latter race, Carlson remained silent while Laura Ingraham, the other member of Fox’s prime-time troika, used her program to criticize Oz and dismiss Hannity’s support.

In each of those races, the candidate backed by a Fox host was able to secure the endorsement of the notoriously Fox-obsessed Trump. Notably, Trump reportedly endorsed Oz and Vance on the advice of Hannity and Carlson, respectively. 

In Arizona, Trump has endorsed Masters, favoring Carlson’s choice over Hannity’s. Masters’ support for Trump’s election lies — and Brnovich’s refusal to participate in them — appears crucial. “Blake knows that the ‘Crime of the Century’ took place, he will expose it and also, never let it happen again,” Trump said in the June statement announcing his endorsement.

The candidate interviews also reflect the varied interests of the hosts. 

When Hannity hosts Brnovich, he typically asks him about the southern border or the cases he is bringing about the Biden administration.

By contrast, there are no typical Masters appearances on Carlson’s show: He’s discussed everything from purportedly “toxic” left-wing children’s books to “obviously innocent” Kyle Rittenhouse’s trial to the left’s “weaponization of our justice system” to “our country's richest African-American entrepreneur” Elon Musk.

Brnovich and Masters appear to greatly value their Fox supporters, prominently displaying the endorsements on their respective websites. 

Visitors to Brnovich’s website are immediately greeted with a popup touting his endorsements from Hannity and fellow Fox host Mark Levin.

The Masters campaign’s Endorsements web page similarly cites Carlson’s support among other GOP luminaries like Trump and Rep. Marjorie Taylor Greene of Georgia.

Brnovich’s Hannity appearances are part of his broader strategy of regularly taking advantage of the Fox airwaves. He has made a total of 63 appearances on Fox weekday shows since launching his campaign, compared to only 11 for Masters.