Donald Trump Endorses Dr. Oz in Pa. Senate Primary: 'He Has Lived with Us Through the Screen'

MANDEL NGAN/AFP via Getty; Noel Vasquez/Getty Donald Trump (left), Dr. Oz

Former President Donald Trump has endorsed Dr. Mehmet Oz in the latter's race for a Pennsylvania Senate seat, saying in a statement released over the weekend that the move "is all about winning elections in order to stop the Radical Left maniacs from destroying our Country."

Even so, the support roiled some loyalists and may continue to test the limits of Trump's appeal to the larger Republican base.

Polls so far indicate Oz is in a close race against hedge fund executive Dave McCormick (and others) for the party nomination.

In his endorsement this weekend, Trump, 75, said he had "known Dr. Oz for many years, as have many others, even if only through his very successful television show. He has lived with us through the screen and has always been popular, respected and smart."

Speaking at a rally in North Carolina , Trump elaborated on his decision — the latest in his string of endorsements, some successful and some not — calling Oz, 61, a "great guy, good man."

"Harvard-educated, tremendous, tremendous career and they liked him for a long time. That's like a poll," Trump told the crowd, The Washington Post reports. "You know, when you're in television for 18 years, that's like a poll. That means people like you."

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Trump's choice ended months of speculation about whom he would ultimately pick in the hotly contested primary, which pits the heart surgeon and popular (and sometimes controversial) TV medical personality against McCormick, the other leading contender for the GOP nod.

Some reports suggested that Trump's decision to endorse Oz over McCormick (who has staffed his campaign with many former Trump aides, including Hope Hicks) may have been the result of his wife, former First Lady Melania Trump.

Another Trump ally, Fox News host Sean Hannity, also recently endorsed Oz.

Noel Vasquez/Getty Images Dr. Mehmet Oz

Both Oz and McCormick entered the race after the leading Republican contender, Sean Parnell, dropped out. Parnell — an Army veteran who had been endorsed by Trump — suspended his campaign in November after losing a custody battle amid allegations of abuse by his estranged wife, which Parnell denied.

Still, not everyone that is a fan of the former president is a fan of Oz.

Parnell tweeted following the endorsement to express his disappointment: "Oz is the antithesis of everything that made Trump the best president of my lifetime—he's the farthest thing from America First & he'd be very bad for PA."

Some other GOP loyalists argued that those close to the former president were "sabotaging" him by convincing him to endorse Oz.

Democratic candidates running for the seat include Pennsylvania's lieutenant governor, John Fetterman.

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Oz officially announced his run for Senate in November, writing in an op-ed for The Washington Examiner that he wanted to "help fix the problems and to help us heal."

Prior to announcing his candidacy, Oz had been living in and and filming his show in New Jersey. He began voting in Pennsylvania's elections via absentee ballot in 2021. His Pennsylvania registration is tied to an address owned by his in-laws, the Associated Press reported.

A spokesperson for The Dr. Oz Show earlier told PEOPLE: "Since last year, Dr. Oz has lived and voted in Pennsylvania where he attended school and has deep family ties."

After he launched his campaign, Sony confirmed that The Dr. Oz Show would come to an end in January, at which time his daughter Daphne Oz's show, The Good Dish, began to fill his slot.