Kevin Hern Wins Oklahoma Senate Seat, Holding Open Seat Vacated by Mullin

Republican Representative Kevin Hern has won Oklahoma's open U.S. Senate seat, defeating Democrat N'Kiyla Jasmine Thomas on Tuesday, November 3, 2026, and keeping the seat in Republican hands. The Kevin Hern Oklahoma Senate victory was projected by the Associated Press on election night, with the race called less than two hours after polls closed at 7 p.m. Central Time. Hern, a four-term congressman from Oklahoma's 1st District, succeeds the seat that Markwayne Mullin gave up in March to become Homeland Security Secretary.

Hern's win came on a midterm night that otherwise brought sweeping Democratic gains across the country, including a projected Democratic takeover of the U.S. Senate.

Key Points

• Republican Rep. Kevin Hern won Oklahoma's open U.S. Senate seat on Tuesday, November 3, 2026, defeating Democrat N'Kiyla Jasmine Thomas.
• The Associated Press projected the win less than two hours after polls closed at 7 p.m. CT, with AP figures showing Hern on 626,824 votes at 97.98 percent of precincts reporting.
• Hern, a four-term congressman from Oklahoma's 1st District since 2018 and endorsed by President Donald Trump, succeeds the seat Markwayne Mullin vacated in March to become Homeland Security Secretary.
• Interim Senator Alan Armstrong, appointed to hold the seat, was barred by state law from seeking a full term.
• On the same night, state legislator Mark Tedford won Hern's vacated 1st District House seat with about 53 percent against Democrat John Croisant.

What Happened

Oklahoma voters went to the polls on Tuesday to fill a Senate seat that had been vacant in electoral terms since Mullin stepped down in March. Although an interim senator had been holding the seat, the November contest decided who would serve the full term, and voters chose Hern, the most familiar Republican name on the ballot after eight years representing the Tulsa-based 1st District in the House.

The result was called quickly. Less than two hours after polls closed, the Associated Press projected Hern as the winner, and as counting continued AP figures showed him with 626,824 votes with 97.98 percent of precincts reporting, confirming a comfortable victory rather than a close contest. Thomas ran in a state where Democrats have not won a U.S. Senate seat in decades, and her share of about 37 percent in the early returns reflected that structural challenge, even on a night when Democrats were winning Senate races in Texas, Kansas and Ohio.

Background and Context

The race began with Mullin's departure. Mullin gave up his Senate seat in March 2026 to become Homeland Security Secretary in President Donald Trump's administration, creating the open seat that Hern and Thomas contested. Under Oklahoma law, Armstrong was appointed to hold the seat on an interim basis, but state law barred him from seeking a full term, so the November election was always going to produce a new senator rather than ratify an incumbent.

Hern entered the race as the best-known Republican contender. First elected to the House in 2018, he had served four terms representing Oklahoma's 1st District, which covers Tulsa and its surrounding communities, and he carried the endorsement of President Trump into the Senate contest. That combination made him the favourite from the outset.

Kevin Hern Oklahoma Senate Win: What It Means for the Delegation

Hern's move from the House to the Senate changes the shape of Oklahoma's delegation in Washington. He leaves a House seat he had held since 2018, and Tedford's victory in that seat on the same night means the delegation's Republican majority is preserved, with a new face in the House and a familiar one promoted to the Senate.

In the Senate, Hern will join a chamber whose control has flipped to the Democrats, a very different environment from the Republican majority that held it before the midterms. As a Republican senator in a Democratic-controlled Senate, his role will be shaped by opposition politics: voting against Democratic priorities, defending the Trump administration's record, and working with the Republican minority on issues where agreement is still possible, such as energy policy and agriculture, both central to Oklahoma's economy.

Reactions

The Associated Press projection, coming less than two hours after polls closed, set the tone for the evening in Oklahoma: a quick, decisive result in a race that had never been rated competitive. Hern's endorsement by President Trump had been a central feature of the campaign, and his victory extends the president's record of backing winning Republican candidates in deep-red states, even on a night when Trump-backed candidates lost high-profile races elsewhere.

Why It Matters

Hern's win matters for three reasons. First, it settles the future of a Senate seat that has been in flux since March, giving Oklahoma a senator elected for a full term rather than an interim appointee barred from seeking the office. Second, it confirms Oklahoma's status as one of the most Republican states in the country, even in a midterm cycle that produced a Democratic wave elsewhere. Third, it shows the limits of that wave: Democrats flipped seats in states where they had not won in decades, but they could not break through in Oklahoma, where the Republican advantage remains overwhelming.

What Happens Next

Hern will resign his House seat and prepare to take his place in the Senate when the new Congress is sworn in in January 2027. Tedford, meanwhile, will take over the 1st District House seat, completing a handover that Oklahoma voters effectively approved twice on Tuesday night: once by electing Hern to the Senate, and once by electing his successor in the House. In the Senate, Hern will serve in the minority, and his early months will reveal how he positions himself within the Republican conference: as a loyal supporter of the Trump administration's agenda, as a voice for Oklahoma's energy and agriculture interests, or as a bridge-builder on the issues where the two parties still find common ground.

Frequently Asked Questions

Who won the Oklahoma Senate race in 2026?

Republican Representative Kevin Hern won the open U.S. Senate seat on Tuesday, November 3, 2026, defeating Democrat N'Kiyla Jasmine Thomas.

Why was the Oklahoma Senate seat open?

The seat became open when Markwayne Mullin gave it up in March 2026 to become Homeland Security Secretary. Interim Senator Alan Armstrong held it but was barred by state law from seeking a full term.

What was the margin of Hern's victory?

Early figures put Hern at about 58 to 59.4 percent against about 37 percent for Thomas. AP figures later showed Hern with 626,824 votes at 97.98 percent of precincts reporting.

Who won Kevin Hern's old House seat?

State legislator Mark Tedford won Hern's vacated 1st District House seat on the same night, with about 53 percent against Democrat John Croisant.

When does Hern take office in the Senate?

Hern will take his Senate seat when the new Congress convenes in January 2027, after resigning his House seat.

Read more: Democrats win Senate control in 2026 midterms, completing Congress sweep and James Talarico stuns Ken Paxton to win Texas Senate seat in historic upset. Also see Peggy Flanagan wins Minnesota Senate race, first Native American woman elected to Senate.