President Trump endorsed Oklahoma Representative Kevin Hern for the U.S. Senate seat vacated by Markwayne Mullin, who was nominated as homeland security secretary. Trump praised Hern as “a true friend of MAGA” in a social media post, solidifying Hern’s position after other GOP contenders declined to challenge him. Senator Mullin’s rapid elevation to cabinet rank created an urgent timeline, with filing deadlines requiring candidates to act swiftly. Governor Kevin Stitt and Representative Stephanie Bice both ruled out runs, leaving Hern as the de facto nominee. The endorsement underscores Trump’s influence in shaping Republican primaries, particularly in deeply conservative states like Oklahoma, where he won all 77 counties in 2020 and 2024.