Gov. Kevin Stitt is weighing five Oklahoma candidates to replace Sen. Markwayne Mullin in the U.S. Senate, according to a source familiar with the selection process.
Mullin was tapped last week as President Donald Trump’s nominee for U.S. secretary of Homeland Security.
Stitt must appoint a replacement within 30 days after Mullin formally vacates the seat.
Who is under consideration
• Nathan Dahm — Served as chair of the Oklahoma Republican Party from 2023 to 2025. Previously served as an Oklahoma state senator from 2012 to 2024.
• David Ostrowe — Currently serves as chief operating officer in the governor’s office.
• John O’Connor — Served as Oklahoma attorney general from 2021 to 2023.
• Dustin Hilliary — Currently serves as a senior advisor to Stitt. Hilliary is co-CEO of Hilliary Communications.
• Harold Hamm — An oil and gas executive and billionaire best known as the founder of Continental Resources and a noteworthy figure in the U.S. shale oil boom.
A second source familiar with the situation tells News 9 that Hilliary was contacted by the governor’s office regarding the Senate appointment.
What happens next
Mullin is scheduled to begin serving as Homeland Security secretary on March 31. Once the seat is vacated, state law gives Stitt 30 days to name a replacement.
The appointment would remain in effect until the next regularly scheduled statewide election.
