Iowa State Senate seat · lines in effect since 2022
Iowa Senate District 18
A district of about 65,000 people, 47% of adults with a bachelor's degree. It votes D+46.0 relative to the nation for president.
2024 election
Nov 5, 2024- Janet Petersen (D) · won97.1%
- Write-ins and other votes (OTH)2.9%
Unopposed.
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 12:13 PM ET
Where it sits among all 50 seats
Every Iowa State Senate seat by partisan lean, from most Democratic to most Republican. Lean is the seat's presidential vote on current lines, relative to the nation.
Democratic
Source: 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET
Every election for this seat
15 races since 1972; the seat changed party 2 times. District numbers are redrawn after each census: each group is one set of lines.
| Year | Winner | Runner-up | Won by |
|---|---|---|---|
| Lines first used in 2022 | |||
| 2024 | Janet Petersen (D) | — | Unopposed |
| Lines first used in 2012 | |||
| 2020 | Janet Petersen (D) | — | Unopposed |
| 2016 | Janet Petersen (D) | — | Unopposed |
| 2012 | Janet Petersen (D) | Vicki Stogdill (R) | 38.2 |
| Lines first used in 2002 | |||
| 2008 | Swati A. Dandekar (D)Flip | Joe Childers (R) | 8.7 |
| 2004 | Mary A. Lundby (R) | Lorna M. Richards (D) | 19.5 |
| Lines first used in 1992 | |||
| 2000 | Michael W. Connolly (D) | Stephen Potts (R) | 14.6 |
| 1996 | Michael W. Connolly (D) | Greg Yoko (R) | 26.0 |
| 1992 | Michael W. Connolly (D) | — | Unopposed |
| Lines first used in 1982 | |||
| 1989 special election | Michael W. Connolly (D) | — | Unopposed |
| 1988 | Bob Carr (D) | — | Unopposed |
| 1984 | Bob Carr (D) | — | Unopposed |
| Lines first used in 1972 | |||
| 1980 | Ted Anderson (D)Flip | Jerry E. Jorgenson (R) | 2.1 |
| 1976 | Willard R. Hansen (R) | Ted Anderson (D) | 4.6 |
| 1972 | Willard R. Hansen (R) | Charles J. Uban (D) | 16.0 |
Won by: the winner's lead over the runner-up, in points of the vote. Source: 99chambers results archive (MEDSL, Klarner, state election offices)
Districts that overlap District 18
The state's districts in other chambers that share residents with this one, and the share of District 18's area in each.
- U.S. House
- IA-3 100%
Who lives here, compared
Grey bars show the spread of all 50 seats. Small marks are other seats in Iowa. The black marker is District 18.
Higher than 82% of seats.
Lower than 90% of seats.
Higher than 67% of seats.
Higher than 94% of seats.
Higher than 82% of seats.
Denser than 98% of seats.
Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current linesUpdated Oct 13, 2026, 5:06 AM ET
Seats most like this one
Nearest seats on demographics, density and lean.
District 4558% college gradsD+55.6Held DDistrict 43
56% college gradsD+40.2Held DDistrict 16
53% college gradsD+18.1Not up in 2026District 40
34% college gradsD+13.7Not up in 2026
Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current lines; 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET