The Associated Press reports that author J.D. Vance has won the Republican Senate primary in Ohio.
Vance defeated former state treasurer Josh Mandel, who had been polling near the top for months.
The Republican nominee will face off against Democratic U.S. Rep. Tim Ryan, the AP reported.
In the GOP primary, Vance defeated state Sen. Matt Dolan, investment banker Mike Gibbons, and former state Republican Party Chair Jane Timken.
Even before Trump endorsed Vance, the race had become a test of Trump-likeness.
The real Trump conservative, according to Timken, is Mandel. The two men have similar business backgrounds.
Many in Ohio were surprised by Trump's endorsement because Vance had previously criticised the former president.
Vance had called Trump "reprehensible" and a "idiot" in2016, but in his primary campaign, he called those remarks "stupid."