2026 Iowa Senate election

Republicans have controlled the Iowa Senate since the 2016 election. They expanded their supermajority in the chamber to 35 seats in the 2024 election, their largest majority since the 1970 election.^[2] They never seated this many Senators, however, as Chris Cournoyer resigned to become lieutenant governor. Democrat Mike Zimmer flipped her seat in the ensuing special election in a major upset, undoing Republicans' net gain from the 2024 election.^[3] Later in 2025, the death of Republican Rocky De Witt led to another special election, which Democrat Catelin Drey won in an upset, breaking the Republican supermajority in the chamber, which they had held since the 2022 elections.^[4] Entering the 2026 election, Republicans hold a 33–17 majority in the Senate.

• District 23: Jack Whitver is retiring.^[6]

• District 17: Izaah Knox is retiring to run for Polk County supervisor.^[7]
• District 43: Zach Wahls is retiring to run for the U.S. Senate.^[8]

The 1st district encompasses the city of Sioux City. The incumbent is Democrat Catelin Drey, who was elected in a special election on August 26, 2025, with 55.2% of the vote.^[10]

The 3rd district encompasses all of Buena Vista, O'Brien, and Osceola counties, as well as parts of Cherokee and Clay counties. The incumbent is Republican Lynn Evans, who was elected in 2022 with 99.1% of the vote.^[11] Evans briefly ran for the U.S. House of Representatives in Iowa's 4th congressional district, but dropped out of the race in July 2025.

He announced that he would instead run for re-election.^[12]

The 5th district encompasses all of Dickinson, Emmet, Kossuth, Palo Alto, and Winnebago counties, as well as part of Clay County. The incumbent is Republican Dave Rowley, who was re-elected in 2022 with 98.5% of the vote.^[11]

Rowley announced he would run for re-election in August 2025.^[13] He was diagnosed with tonsil cancer in early 2026, but has said this does not affect his plans to run for re-election.^[14]

The 7th district encompasses all of Monona County, most of Woodbury County, and parts of Cherokee and Plymouth counties. The incumbent is Republican Kevin Alons, who was elected in 2022 with 98.0% of the vote.^[11] He is running for re-election.^[15]

The 9th district encompasses all of Adams, Cass, Montgomery, Page, and Ringgold counties, as well as most of Union County. The incumbent is Republican Tom Shipley, who was re-elected in 2022 with 76.9% of the vote.^[11]

The 11th district encompasses all of Warren County and part of Marion County. The incumbent is Republican Julian Garrett, who was re-elected in 2022 with 61.6% of the vote.^[11] After a prostate cancer diagnosis, Garrett announced he would not be seeking re-election.^[16]

The 13th district encompasses all of Davis, Monroe, and Wapello counties and part of Appanoose County. The incumbent is Republican Cherielynn Westrich, who was elected in 2022 with 64.9% of the vote.^[11]

The 15th district encompasses southern Des Moines, including the Des Moines International Airport. The incumbent is Democrat Tony Bisignano, who was re-elected in 2022 with 95.3% of the vote.^[11]

The 17th district encompasses central Des Moines. The incumbent is Democrat Izaah Knox, who was elected in 2022 with 76.6% of the vote.^[11] Knox is not seeking re-election, as he is running for Polk County Supervisor.^[17]

The 19th district encompasses all of Jasper County as well as parts of Mahaska and Marion counties. The incumbent is Republican Ken Rozenboom, who was re-elected in 2022 with 68.6% of the vote.^[11] Rozenboom is not running for re-election.^[18]

The 21st district encompasses the city of Ankeny. The incumbent is Republican Mike Bousselot, who was elected in 2022 with 50.9% of the vote.^[11] In April 2025, Bousselot formed an exploratory committee to explore running for governor in 2026, but ultimately decided to run in District 23.^[19][20]

The 23rd district encompasses parts of Dallas and Polk counties. The incumbent is Republican Jack Whitver, who was re-elected in 2022 with 58.6% of the vote.^[11]

On September 16, 2025, he announced that he would not seek re-election.^[6]

Mike Bousselot is running with Whitver's support.^[20] He is overwhelmed with the thought of running for re-election in District 21, so he is moving out to a "safer" seat. ^[21]

Tony Thompson is the Democrat running for this seat.^[22]

The 25th district encompasses the city of Ames. The incumbent is Democrat Herman Quirmbach, who was re-elected in 2022 with 75.7% of the vote.^[11]

The 27th district encompasses all of Grundy, Hardin, and Poweshiek counties, most of Tama County, and part of Black Hawk County. The incumbent is Republican Annette Sweeney, who was re-elected in 2022 with 66.6% of the vote.^[11] She is running for re-election.^[23]

The 29th district encompasses all of Bremer, Butler, and Chickasaw counties, as well as most of Floyd County. The incumbent is Republican Sandy Salmon, who was elected in 2022 with 65.4% of the vote.^[11]

The 31st district encompasses the city of Waterloo. The incumbent is Democrat William Dotzler, who was re-elected in 2022 with 96.9% of the vote.^[11]

The 33rd district encompasses most of Dubuque and Jackson counties, as well as all of Jones County. The incumbent is Republican Carrie Koelker, who was re-elected in 2022 with 65.8% of the vote.^[11]

The 35th district encompasses all of Clinton County and parts of Jackson and Scott counties. The incumbent is Democrat Mike Zimmer, who was elected in a 2025 special election with 51.7% of the vote.^[24]

The 37th district encompasses the city of Marion. The incumbent is Democrat Molly Donahue, who was elected in 2022 with 56.0% of the vote.^[11]

The 39th district encompasses southern Cedar Rapids. The incumbent is Democrat Liz Bennett, who was elected in 2022 with 64.8% of the vote.^[11]

The 41st district encompasses all of Cedar County, as well as parts of Muscatine and Scott counties. The incumbent is Republican Kerry Gruenhagen, who was elected in 2022 with 58.1% of the vote.^[11]

The 43rd district encompasses the cities of North Liberty, Coralville, and Solon. The incumbent is Democrat Zach Wahls, who was re-elected in 2022 with 97.5% of the vote.^[11]

Wahls is retiring to run for US Senate.^[8]

The 45th district encompasses the city of Iowa City. The incumbent is Democrat Janice Weiner, who was elected in 2022 with 82.0% of the vote.^[11] She is running for re-election.^[25]

The 47th district encompasses the cities of Bettendorf and Eldridge. The incumbent is Republican Scott Webster, who was elected in 2022 with 56.1% of the vote.^[11]

Ophthalmologist Dr. Nikhil Wagle, who is also a Pleasant Valley School board member, announced in August 2025 that he would run for this seat.^[26]