Mar 25, 2026 - The Senate confirmed Sen. Markwayne Mullin, R-Oklahoma, as secretary of the Department of Homeland Security on Monday night in a 54-45 vote.
Mullin, who resigned from the Senate earlier this week to take the position, succeeds Kristi Noem, whom President Donald Trump removed from the role earlier in March. The confirmation came after the Senate voted 54-37 on Sunday to advance the nomination out of procedural debate.
Mullin, 48, has served as Oklahoma's junior senator since January 2023. He previously represented Oklahoma's 2nd Congressional District in the House of Representatives from 2013 to 2023. An enrolled member of the Cherokee Nation, Mullin is a former businessman and plumber who took over his family's plumbing company before entering politics. He also owns a ranch in Westville, Oklahoma.
The Department of Homeland Security oversees immigration enforcement, border security, cybersecurity, disaster response through the Federal Emergency Management Agency, and transportation security through the Transportation Security Administration. The agency has faced operational challenges in recent weeks, including a partial shutdown that began in mid-February.
Mullin's nomination advanced quickly through the Senate Homeland Security and Governmental Affairs Committee. During his confirmation hearing on March 18, senators questioned him on border security policies, immigration enforcement priorities and agency management. A small number of senators from both parties crossed party lines during the procedural and final votes.
Republicans hold a 53-45 majority in the Senate, with two independents who caucus with Democrats. Mullin did not vote on his own confirmation after resigning his Senate seat. The vote largely followed party lines, with one Democrat supporting advancement in committee and limited crossover support on the floor.
The confirmation returns stability to the department's leadership after a period of transition. Noem had served as the first DHS secretary in Trump's second term before her removal.
As of Tuesday, Mullin had not yet been sworn in, though White House officials indicated the ceremony would occur shortly. The Department of Homeland Security continues its operations under acting leadership pending the new secretary's formal assumption of duties. No immediate policy announcements were made following the vote.