Vance is best-known for writing “Hillbilly Elegy,” a New York Times bestseller documenting the political changes among working class white people in the beleaguered region of Appalachia. He initially mocked and rejected Trump in 2016 but later became a vocal supporter of his policies.

“Like some others, J.D. Vance may have said some not so great things about me in the past, but he gets it now, and I have seen that in spades,” said Trump in his endorsement in April. “He is our best chance for victory in what could be a very tough race.”

The race was largely seen as a test of the political influence Trump held within the Republican party as some elements have attempted to move forward without him.

Heading into the primary election, Mandel and Vance were within the error of margin in the latest Fox News poll.

First-term Republican Gov. Mike DeWine defeated conservative primary challengers and garnered the Republican gubernatorial nomination. DeWine faced opponents who tried to capitalize on anger over the governor’s pandemic lockdown policies. He will go up against Nan Whaley, the Democratic gubernational nominee.

Vance will go up against Tim Ryan, the Democratic senatorial nominee. They are vying to fill in the seat vacated by Sen. Rob Portman, a Republican, who is not running for re-election.

Here’s more about the GOP Senate primary race:

Ohio Senate Primary