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12 DAYS OUT
GA GovBottoms D +0.6SC SenAndrews D +1.4NE GovPillen R +1.5AK SenPeltola D +1.6IA SenTurek D +2.1ME SenJackson D +2.2TX SenTalarico D +2.4TX GovAbbott R +2.6KS GovHolscher D +2.6WI GovCrowley D +2.7KS SenHamilton D +2.8NE SenOsborn I +3.0MI SenEl-Sayed D +3.0NV GovFord D +3.3OH SenBrown D +3.7OH GovActon D +4.1
2026 state legislative forecast

South Dakota Senate forecast

Republicans win control of the South Dakota Senate in nearly every one of 2,000 simulations, against a Republican majority today. All 35 seats are on the 2026 ballot; 0 races are within a 35 to 65 split.

Safe RUpdated October 22, 2026Seats 35On the ballot 35South Dakota HouseAll chambers
Chance of control
<1%D>99%R
Democratic seats, 80% range
4 to 7
Median 5 · 18 for a majority
Favored to flip
2to D0to R
After 2024: 3 D, 32 R
Environment
D +11.2
Shift from the 2024 presidential vote

South Dakota Senate map

District 1: Democrats <1%District 2: Democrats <1%District 3: Democrats <1%District 4: Democrats <1%District 5: Democrats <1%District 6: Democrats <1%District 7: Democrats <1%District 8: Democrats <1%District 9: Democrats <1%District 10: Democrats >99%District 11: Democrats 35%District 12: Democrats 68%District 13: Democrats <1%District 14: Democrats <1%District 15: Democrats 98%District 16: Democrats <1%District 17: Democrats <1%District 18: Democrats 9%District 19: Democrats <1%District 20: Democrats <1%District 21: Democrats <1%District 22: Democrats <1%District 23: Democrats <1%District 24: Democrats <1%District 25: Democrats <1%District 26: Democrats 33%District 27: Democrats 97%District 28: Democrats <1%District 29: Democrats <1%District 30: Democrats <1%District 31: Democrats <1%District 32: Democrats 92%District 33: Democrats <1%District 34: Democrats 13%District 35: Democrats <1%1345781617181920212223242526272829303132333435
Safe DLean DToss upLean RSafe R

District shapes are estimated from where each district's voters live in the precinct returns, not drawn from the official boundary files.

Pick a district

Hover the map for the odds in any district. Click one to pin it here and find it in the table below.

Every seat

Average 6 D to 30 R
District 10: Democrats win >99%District 15: Democrats win 98%District 27: Democrats win 97%District 32: Democrats win 92%District 12: Democrats win 68%District 11: Democrats win 35%District 26: Democrats win 33%District 34: Democrats win 13%District 18: Democrats win 9%District 1: Democrats win <1%District 2: Democrats win <1%District 3: Democrats win <1%District 4: Democrats win <1%District 5: Democrats win <1%District 6: Democrats win <1%District 7: Democrats win <1%District 8: Democrats win <1%District 9: Democrats win <1%District 13: Democrats win <1%District 14: Democrats win <1%District 16: Democrats win <1%District 17: Democrats win <1%District 19: Democrats win <1%District 20: Democrats win <1%District 21: Democrats win <1%District 22: Democrats win <1%District 23: Democrats win <1%District 24: Democrats win <1%District 25: Democrats win <1%District 28: Democrats win <1%District 29: Democrats win <1%District 30: Democrats win <1%District 31: Democrats win <1%District 33: Democrats win <1%District 35: Democrats win <1%
Safe DLean DToss upLean RSafe R
Democratic seats across 2,000 simulations
18 for a majority0911

Every Senate district

DistrictLast winner2026 nominees2024 leanForecastDem winProjected D votesProjected R votesTotalRating
26Tamara Grove 2024Shawn Bordeaux vs Rebecca ReimerR +12.8R +2.533%3,2013,3696,670Lean R
11Chris Karr 2024Aaron Matson vs Chris KarrR +9.8R +2.635%5,0955,37110,625Lean R
12Arch Beal 2024Joe Zweifel vs Kari Shanard-KoendersR +5.3D +2.968%5,0454,7619,955Lean D
34Taffy Howard 2024Michael Calabrese vs Taffy HowardR +16.5R +7.413%5,0895,90511,162Likely R
32Helene Duhamel 2024Jeff Shelton vs Helene DuhamelR +1.8D +9.492%4,3373,5928,050Likely D
18Lauren Nelson 2024Kay Swihart vs Lauren NelsonR +26.6R +9.69%4,2975,2099,651Likely R

Projected South Dakota Senate vote

35 seats on the ballot
PartyVotesShare
Democrats50,20113.6%
Republicans310,55384.1%
Independents and others8,3022.2%
Total369,058100%

The sum of every district on the ballot. Each district's turnout is its 2024 top of ticket vote on today's lines, scaled to the forecast's 2026 statewide vote less a small share who skip legislative races, split by the district forecast. A district with no candidate from one party gives all its votes to the other. The district table lists each seat's projected votes.

How this is built
Each district starts from its 2024 presidential vote, read off the precincts that voted in it, and moves with the state's 2026 House forecast and the national generic ballot. Half of what the last legislative winner ran ahead of the district carries over, 2026 primary turnout moves districts where it is posted, and district and statewide legislative polls count by recency and sample. A seat with no candidate from one party is called for the other. 2,000 simulations share a national, a state and a district shock. The map's district shapes are estimated from where each district's voters are in the precinct returns. All chambers.