Iowa Senate
2026 forecast. Updated October 22, 2026, 09:28 UTC
25 of 50 seats are up in 2026. Democrats are forecast to hold 16 seats after November (80% range 15–18) and Republicans 34 (32–35). In 1 seat a Democrat or Republican faces only independents or minor-party candidates and is counted as winning; in 2018 to 2024 such candidates lost about 3% of the time, mostly to sitting independents.
Initial version. This model was tested on every state legislative election from 1994 to 2024 before publication, forecasting each as if it had not happened. It beat the simple rule “the party that holds the seat keeps it”, and its chamber seat counts were off by 2.9 seats on average (target: under 3). Districts with no two-party race last time are read from their own presidential vote, a change tested in advance that cut their average error from 17 to 13 points. It missed one of its five accuracy targets: in 2024, the calmest year on record, its ranges were wider than they needed to be (92% of results fell inside its 80% ranges; target: at most 88%). Treat the ranges as cautious. The full test record and code.
Go to a district
Shaded by the chance of a Democratic win; pale dashed chips are not up in 2026.
Districts
Chance: of a Democratic win (in a district electing several members, of Democrats winning at least half its seats). Source: where the candidate list came from.
| District | Status | Candidates | Democratic chance | Source |
|---|---|---|---|---|
| 1 | Forecast | Christopher Prosch (R), Catelin Drey (D) | 39% | official |
| 2 | Not up in 2026 (held by Republican) | |||
| 3 | Forecast | Lynn Evans (R), Mike Frantz (D) | 4% | official |
| 4 | Not up in 2026 (held by Republican) | |||
| 5 | No Democrat running: counted Republican | Dave Rowley (R), Rachel Gravert (independent) | official | |
| 6 | Not up in 2026 (held by Republican) | |||
| 7 | Decided: only a Republican is running | Kevin Alons (R) | official | |
| 8 | Not up in 2026 (held by Republican) | |||
| 9 | Forecast | James Uhlenkamp (D), Steve Baier (R) | <1% | official |
| 10 | Not up in 2026 (held by Republican) | |||
| 11 | Forecast | Hollie Arlene Zajicek (R), Sinikka Waugh (D) | 3% | official |
| 12 | Not up in 2026 (held by Republican) | |||
| 13 | Forecast | Jeff Kulmatycki (R), Brenda Case (D) | 1% | official |
| 14 | Not up in 2026 (held by Democrat) | |||
| 15 | Decided: only a Democrat is running | Tony Bisignano (D) | official | |
| 16 | Not up in 2026 (held by Democrat) | |||
| 17 | Forecast | Ronald Langston (R), Samy El-Baroudi (D) | 95% | official |
| 18 | Not up in 2026 (held by Democrat) | |||
| 19 | Forecast | Barb Kniff McCulla (R), Zachary Mecham (D) | <1% | official |
| 20 | Not up in 2026 (held by Republican) | |||
| 21 | Forecast | John Hollinrake (R), Heather Matson (D) | 56% | official |
| 22 | Not up in 2026 (held by Democrat) | |||
| 23 | Forecast | Tony Thompson (D), Wes Enos (R) | 7% | official |
| 24 | Not up in 2026 (held by Republican) | |||
| 25 | Forecast | Paul Wacker (R), Herman C Quirmbach (D) | 96% | official |
| 26 | Not up in 2026 (held by Republican) | |||
| 27 | Decided: only a Republican is running | Annette Sweeney (R) | official | |
| 28 | Not up in 2026 (held by Republican) | |||
| 29 | Forecast | Sandy Salmon (R), Jim Vowels (D) | <1% | official |
| 30 | Not up in 2026 (held by Republican) | |||
| 31 | Decided: only a Democrat is running | Timi Brown Powers (D) | official | |
| 32 | Not up in 2026 (held by Republican) | |||
| 33 | Forecast | Carrie Koelker (R), Mary Ungs-Sogaard (D) | <1% | official |
| 34 | Not up in 2026 (held by Republican) | |||
| 35 | Forecast | Joe Stutting (R), Mike Zimmer (D) | 8% | official |
| 36 | Not up in 2026 (held by Democrat) | |||
| 37 | Forecast | Randy Marzen (R), Molly Donahue (D) | 97% | official |
| 38 | Not up in 2026 (held by Republican) | |||
| 39 | Forecast | Edward Bernie Hayes (R), Liz Bennett (D) | >99% | official |
| 40 | Not up in 2026 (held by Democrat) | |||
| 41 | Forecast | Kerry Gruenhagen (R), Tom Wieck (D) | 4% | official |
| 42 | Not up in 2026 (held by Republican) | |||
| 43 | Decided: only a Democrat is running | Meghann Foster (D) | official | |
| 44 | Not up in 2026 (held by Republican) | |||
| 45 | Decided: only a Democrat is running | Janice Weiner (D) | official | |
| 46 | Not up in 2026 (held by Republican) | |||
| 47 | Forecast | Scott Webster (R), Nikhil Wagle (D) | 8% | official |
| 48 | Not up in 2026 (held by Republican) | |||
| 49 | Forecast | Cynthia Mensendick (R), Cindy Winckler (D) | 96% | official |
| 50 | Not up in 2026 (held by Republican) |