Republican Gov. Kevin Stitt of Oklahoma will appoint energy executive Alan Armstrong to the U.S. Senate seat vacated by Markwayne Mullin, who was confirmed Monday as the new Secretary of Homeland Security in a 54-45 Senate vote.
Mullin’s confirmation comes after President Donald Trump fired Kristi Noem earlier this month.
Noem’s tenure was marked by controversy over deadly ICE shootings in Minneapolis and a congressional grilling over $220 million in wasted advertising spending that featured the former secretary. Mullin’s last day in the Senate will coincide with Noem’s last day at DHS — March 31.
Stitt and Trump reportedly met at Mar-a-Lago over the weekend to finalize the selection of Armstrong as Mullin’s replacement. Stitt has scheduled a press conference for Tuesday morning to formally introduce his pick.
Armstrong is chairman of Williams Companies, a Tulsa-based energy company that operates in more than 25 states. He served as CEO for more than a decade before moving to the chairman role. He is a University of Oklahoma graduate with a degree in civil engineering.
Williams Companies employs roughly 5,000 people, and its pipelines handle nearly a third of the natural gas consumed in the United States each day.
Armstrong would serve as a temporary senator until the winner of the November 2026 general election is sworn in. Trump has already endorsed Rep. Kevin Hern in the Republican primary, who announced he will give up his House seat to run for the full term.
Mullin’s 54-45 confirmation was largely along party lines, but Democratic Sens. John Fetterman of Pennsylvania and Martin Heinrich of New Mexico crossed the aisle to confirm him. Sen. Rand Paul, R-Ky., was the lone Republican to vote no after years of tension between the two.
“My goal in six months is that we’re not the lead story every single day,” Mullin said. “My goal is for people to understand we’re out there, we’re protecting them, and we’re working with them.”
Senate Majority Leader John Thune praised the new secretary on the floor Monday.
“Just a few weeks after being elected to the House, when the Oklahoma delegation was touring storm damage, Markwayne cut away from the other Congressmen and climbed through debris to try to shut off water shooting through the wreckage,” Thune said. “See a problem? Take action to solve it. That’s Markwayne.”
Mullin inherits a DHS that has been partially shut down for more than five weeks after Democrats refused to fund the agency. More than 400 TSA agents have quit since the shutdown began, and airport security lines have grown to hours-long waits at major airports after staff has gone unpaid for over a month.
Asked about the new secretary Monday, Trump told reporters: “He’s going to be fantastic.”