Iowa State Senate seat · lines in effect since 2022
Iowa Senate District 15
A district of about 62,000 people, 23% Hispanic, 22% of adults with a bachelor's degree. It votes D+18.5 relative to the nation for president.
2026 election
Nov 3, 2026- Tony Bisignano (D) · won · incumbent97.0%
- Write-in (OTH)3.0%
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
17 races since 1968; the seat changed party 5 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 | |||
| 2026 | Tony Bisignano (D) | Write-in (I) | 94.0 |
| 2022 | Tony Bisignano (D) | — | Unopposed |
| Lines first used in 2012 | |||
| 2018 | Zach Nunn (R)Flip | Dan Nieland (D) | 13.9 |
| 2014 | Chaz Allen (D) | Crystal Bruntz (R) | 5.1 |
| Lines first used in 2002 | |||
| 2010 | Robert E. Dvorsky (D) | Christopher Peters (I) | 49.1 |
| 2006 | Robert E. Dvorsky (D) | — | Unopposed |
| 2002 | Robert E. Dvorsky (D) | Jack Young (R) | 19.3 |
| Lines first used in 1992 | |||
| 1998 | Betty Soukup (D)Flip | Allen Borlaug (R) | 0.6 |
| 1994 | Allen Borlaug (R) | James A. Erb (D) | 14.8 |
| Lines first used in 1982 | |||
| 1990 | Allen Borlaug (R)Flip | Kenneth D. Scott (D) | 3.7 |
| 1986 | Kenneth D. Scott (D)Flip | Paul Bunge (R) | 1.3 |
| 1982 | Arthur L. Gratias (R) | Gary Bernau (D) | 15.0 |
| Lines first used in 1972 | |||
| 1978 | Bob Rush (D) | Lloyd E. Humphreys (R) | 9.2 |
| 1974 | Steve Sovern (D)Flip | Ralph W. Potter (R) | 13.8 |
| 1972 | Ralph W. Potter (R) | Bernard Beuter (D) | 17.7 |
| Lines first used in 1962 | |||
| 1968 special | Edward E. Nicholson (R) | Karl H. Hellman (D) | 31.3 |
| 1968 | Harold A. Thordsen (R) | Joseph W. Cassidy (D) | 0.2 |
Primaries: 2014 Republican primary
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 15
The state's districts in other chambers that share residents with this one, and the share of District 15'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 15.
Lower than 84% of seats.
Lower than 76% of seats.
Higher than 98% of seats.
Higher than 82% of seats.
Higher than 96% of seats.
Denser than 86% 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 126% Hispanic · 22% college gradsR+9.4Held DDistrict 17
22% college gradsD+38.5Held DDistrict 49
26% college gradsD+11.2Held DDistrict 20
29% college gradsR+3.4Not 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
Who has held it
These lines took effect in 2022.
- Tony Bisignano (D)
2023– · Won 2022 by 90.6, 2026 unopposed
Source: Past results: 99chambers results archive (MEDSL, Klarner, state election offices)