OKLAHOMA CITY –Oklahoma Gov. Kevin Stitt announced his pick to replace U.S. Sen. Markwayne Mullin, who will be vacating his congressional seat to serve as secretary of the Department of Homeland Security.
In a news conference on Tuesday, Stitt said he will be appointing Oklahoma energy executive Alan Armstrong to fill Mullin’s seat in the U.S. Senate.
Alan Armstrong is chairman of Williams Companies, a Tulsa-based natural gas infrastructure company operating in more than 25 states. He joined the company nearly 40 years ago and later served more than a decade as CEO before becoming chairman.
Armstrong graduated from the University of Oklahoma with a degree in civil engineering.
Armstrong’s career has centered on expanding natural gas pipeline systems that deliver energy across the United States. He has also been involved in high-profile projects in the Northeast, where regulatory challenges have slowed or blocked development.
Armstrong emerged as the leading candidate after several early contenders lost momentum or withdrew from consideration. Those included energy executive Harold Hamm, once viewed as a frontrunner, and Dustin Hilliary, who removed himself from consideration.
Stitt began signaling his decision privately late last week, and word spread quickly among political and Republican leadership circles, NOTUS journalist Reese Gorman said.
Gorman broke the news of the expected appointment over the weekend and talked to Oklahoma’s Own Scott Mitchell about the development.
Gorman said yes; Stitt initially considered a run for the seat.
Stitt met with national Republican leaders, including Trump and Senate leadership, to gauge potential support but ultimately determined there was no clear path to victory.
When will Armstrong begin serving in the U.S. Senate?
According to President Donald Trump’s announcement about Mullin taking over as head of DHS, Mullin would begin that role at the end of March.
Armstrong is expected to be sworn into the Senate quickly, determine whether to retain existing staff or hire new staff, and immediately begin taking on legislative responsibilities.
Armstrong will serve in the Senate until the November election, when voters will choose who will officially take the seat.
U.S. Rep. Kevin Hern announced he will seek to fill the seat in the next election.
Hern said he was the “most prepared” candidate running and emphasized his alignment with former President Donald Trump and conservative policies.
President Trump endorsed Hern in a statement on Truth Social the day after Hern announced his candidacy.
President Trump decided to replace Kristi Noem as Secretary of the DHS, following tensions over congressional testimony about a federal advertising campaign.
The full Senate confirmed Markwayne Mullin as the new Department of Homeland Security Secretary in a 54-45 vote Monday night.
Democratic Sens. John Fetterman of Pennsylvania and Martin Heinrich of New Mexico voted in favor of Mullin’s confirmation. Sen. Rand Paul of Kentucky was the sole Republican to oppose Mullin.
