Alan Armstrong sworn into Senate to replace Mullin

Oklahoma Republican Alan Armstrong was sworn into the Senate on Tuesday to fill the seat of Markwayne Mullin, who resigned Monday to become the new Homeland Security secretary.

Gov. Kevin Stitt (R-OK) officially announced the energy executive's selection at a press conference in Oklahoma City earlier in the day.

"Alan's story, as you guys get to know him, reflects the very best of Oklahoma — our values, our work ethic, and our pursuit of the American dream that is alive and well in the state of Oklahoma," the governor said.

Sen. Armstrong, whom Gov. Stitt described as a "strong business leader" who believes in "free markets and limited government," was most recently the executive chair of Williams Companies, a natural gas company based in Tulsa, where he had worked for four decades, including as president and CEO.

"This was definitely a tough decision on one hand," he said of his appointment. "But on the other hand, it was kind of a no-brainer, because I really wouldn't want to be sitting around in my retirement thinking, 'gosh, I could've contributed and done something.'"

He will serve in the seat until a successor is elected in November in a special election. Rep. Kevin Hern (R-OK) is the favorite to succeed him, having won President Trump's endorsement days after announcing his bid earlier this month.

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