Sen. Cynthia Lummis (R-Wyo.) announced on Dec. 19, 2025, that she will not seek re-election to the U.S. Senate in 2026.

Lummis posted on X, “Deciding not to run for reelection does represent a change of heart for me, but in the difficult, exhausting session weeks this fall I’ve come to accept that I do not have six more years in me. I am a devout legislator, but I feel like a sprinter in a marathon. The energy required doesn’t match up.”

In 2020, Lummis ran for her sole term representing Wyoming in the U.S. Senate after then-Sen. Mike Enzi (R) announced he would not seek re-election. In the general election, she defeated Merav Ben-David (D) 73% to 27%.

As of Dec. 16, independent race forecasters The Cook Political Report, Inside Elections, and Sabato’s Crystal Ball rated the general election for the seat as Solid/Safe Republican.

As of Dec. 19, Lummis is one of 52 members of Congress — nine U.S. senators and 43 U.S. House members — who have announced they will not seek re-election to their current seats in 2026.

Of the senators not running for re-election, eight — Lummis, Joni Ernst (R-Iowa.), Thom Tillis (R-N.C.), Dick Durbin (D-Ill.), Jeanne Shaheen (D-N.H.), Mitch McConnell (R-Ky.), Tina Smith (D-Minn.), and Gary Peters (D-Mich.) — announced their retirements from public office, while the other, Sen. Tommy Tuberville (R-Ala.), is running for governor of Alabama.

Compared to the last four election cycles, there were seven Senate retirement announcements at this point in 2024, six in 2022, four in 2020, and two in 2018.

Between January 2011 and December 2025, 51 U.S. Senate incumbents announced they would not seek re-election. During that period, an average of three incumbents announced their retirement plans each year. January had the highest number of members announcing they would not run for re-election at 12. The fewest announcements took place in April, June, July, August, and December at one each.