Kevin Hern secured the Republican nomination for Oklahoma’s open U.S. Senate seat in the June 2026 primary with roughly 70 percent of the vote after receiving an early endorsement from President Trump, clearing the field in a state that has not elected a Democrat to the chamber since 1990. The vacancy arose when former Senator Markwayne Mullin resigned to become Homeland Security Secretary, and state rules barred the appointed interim holder from seeking a full term. Hern, a four-term House member with strong name recognition and fundraising in the Tulsa area, faces Democratic nominee N’Kiyla “Jasmine” Thomas, a nurse who advanced through an August runoff. Traders assign Hern a 97.6 percent implied probability, reflecting Oklahoma’s consistent Republican voting patterns and the absence of recent polling or events that would narrow the contest. A major scandal, health development, or unprecedented turnout shift would be required to alter the outcome before the November 3 general election.