(WASHINGTON) — Bill Hagerty, a former diplomat who was endorsed by Donald Trump, won a contentious Senate primary in Tennessee on Thursday night, reinforcing the strength of a presidential endorsement in some of the nation’s reddest territory.

Hagerty toppled Dr. Manny Sethi, an orthopedic trauma surgeon who garnered support from Sens. Ted Cruz, R-Texas, and Rand Paul, R-Ky., to secure the Republican nomination in the race to replace the retiring Sen. Lamar Alexander. Hagerty led Sethi by double digits when The Associated Press called the race, with his victory not only boosting Trump’s endorsement record but also delivering an answer about who voters in the state believe is the true conservative — a key argument that played out throughout the final stretch of the contest.

“President Trump has had my back since before the beginning of all of this,” Hagerty said during his victory speech. “Thank you for being the inspiration to me, President Trump. I look forward to helping you continue moving forward and to see another four years.”

The race turned into a pitched battle over fealty to the president, with Hagerty centering his campaign on his relationship with Trump. The former private equity executive served as an ambassador to Japan under Trump, was a high-dollar fundraiser fo the president’s 2016 campaign and volunteered as Trump’s Tennessee Victory Chair. He also held a senior role during Trump’s transition.

The president essentially launched Hagerty’s campaign in a tweet in July 2019, and he campaigned for Hagerty via tele-town halls. Members of the Trump family also were featured prominently in Hagerty’s ads, underscoring his connections to the first family and his allegiance to Trump.

Sethi pitched himself as a loyalist to Trumpism and conservative ideals that ground the party — a similar theme seen throughout this year’s primary cycle. In a final stretch of the race, which turned ugly, Sethi’s insurgent bid gained some late momentum, boosted by grassroots energy, making the contest far more competitive than anticipated.

The race devolved into a duel over who could out-Trump the other, as both Cruz and Paul saw Sethi as the “true conservative.”

As Sethi’s challenge proved to be a concern, Hagerty sought to paint Sethi as “too liberal for Tennessee,” suggesting in ads that he donated to Democrats instead of Trump. With Hagerty widely considered the front-runner with Trump’s support, Sethi used Hagerty’s ties to Sen. Mitt Romney, a frequent foe of the president, to cast the former national finance chair for Romney’s 2008 presidential campaign as “Mitt Romney’s guy” and undercut his key selling point.

Earlier this week, Sethi, a physician, called on Trump to fire Dr. Anthony Fauci, the nation’s leading infectious disease expert, and also defended the use of hydroxychloroquine as a treatment for COVID-19 — a drug Trump has frequently touted.

“I’ve had about enough of this guy Fauci. If I’m President Trump, I call Dr. Fauci into the Board room and tell him, ‘You’re fired,"” he said in a statement, as Fauci and Trump have been at odds over aspects of the administration’s response to the coronavirus.

This race wasn’t the first in which the president and Cruz clashed over an anointed selection in a Republican primary. In Texas’ 23rd Congressional District, the Trump-endorsed Tony Gonzales, a former Navy cryptologist, appears to be the winner over Cruz-backed Raul Reyes, Jr., a lieutenant colonel in the Air Force.

Ultimately, Hagerty winning a tough primary in a state Trump carried by 26 points in 2016 signals that that president’s endorsement is valuable and that he continues to have considerable sway over GOP voters.

Now, Hagerty is set to square off in the fall against Marquita Bradshaw, an activist from Memphis, who delivered a stunning upset in the Democratic primary on Thursday.

Bradshaw, a political newcomer, was one of two African Americans in the Democratic race, and she defeated James Mackler, a former Army helicopter pilot who had the backing of the national Democratic establishment since January. To underscore how surprising Bradshaw’s win is, in her most recent filing with the FEC from April, she raised $8,420, compared to Mackler’s $410,938 during the same period. He’s raised $2.1 million for the cycle. She has not filed since then.

Mackler entered the night seen as the likely challenger in the fall for the safe red seat, but his loss breaks the DSCC’s winning streak, with all of their other primary candidates succeeding in their races so far this cycle. Bradshaw earned 36% of the vote, compared to Mackler’s 24%, a blow to national Democrats.

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