Wisconsin State Senate seat · lines in effect since 2024
Wisconsin Senate District 31
A district of about 179,000 people, 33% of adults with a bachelor's degree. It votes D+3.2 relative to the nation for president.
Where it sits among all 33 seats
Every Wisconsin 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 race on these lines
Results recomputed from precinct returns as if today's boundaries had always existed, so years compare like for like.
| 2024 | 2026 | |
|---|---|---|
| U.S. Senate | D+4.7 | No race |
| Wisconsin State Senate | No race | D+16.9 |
Outlined: the race for this seat itselfBlank: no race that year
Source: 99chambers results archive: precinct results allocated to current lines; 2026: civicAPIUpdated Nov 7, 2026, 3:01 PM ET
Who lives here, compared
Grey bars show the spread of all 33 seats. Small marks are other seats in Wisconsin. The black marker is District 31.
Higher than 72% of seats.
Higher than 50% of seats.
Lower than 94% of seats.
Lower than 62% of seats.
Higher than 59% of seats.
Less dense than 59% 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. 1 of the 4 flipped this year.
District 3232% college gradsD+3.6Not up in 2026District 14
27% college gradsD+2.3Not up in 2026District 9
26% college gradsR+15.8Held RDistrict 17
29% college gradsD+2.4Flipped D
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 2024.
- Jeff Smith (D)
2027– · Won 2026 by 16.9
Source: Past results: 99chambers results archive (MEDSL, Klarner, state election offices)