Sen. John Cornyn (R-Texas), a member of the Senate Finance Committee lost his Republican primary runoff Tuesday to Texas Attorney General Ken Paxton, according to national news outlets.
Paxton, recently endorsed by President Donald Trump, won about 64% of the vote in the GOP runoff, according to Wednesday morning data from NBC News.
The winner will face Democrat James Talarico, a member of the Texas House of Representatives, in the November general election. In March, Talarico defeated U.S. Rep. Jasemine Crockett in the Texas Democratic Party primary.
Cornyn was first elected to the Senate in 2002. Paxton became Texas attorney general in 2015 and later withstood a 2023 impeachment vote in the GOP-majority Texas House of Representatives.
Cornyn supported several nuclear energy bills during his time in the Senate. In 2024, Cornyn, along with Sens. Alex Padilla (D-Calif.), Cory Booker (D-N.J.), Patty Murray (D-Wash.) and Todd Young (R-Ind.), introduced the Fusion Energy Act that codified the Nuclear Regulatory Commission to pursue a separate regulatory pathway for fusion energy from fission energy systems.
The Fusion Energy Act was signed into law as a part of the Fire Grants and Safety Act in 2024.
Cornyn and Padilla also introduced a Senate companion bill called Office of Fusion Act of 2025 in December 2025 which would codify the Office of Fusion as a standalone under the Department of Energy. This bill comes after DOE reorganized its agency in November 2025 and included a newly established office dedicated to fusion energy.