United States / South Dakota / Senate Election
2026 United States Senate election in South Dakota
South Dakota polling average: Rounds (R) 50.7% — Bengs (I) 40.3% — Rounds (R) +10.4Pollytic average to 26 Oct 2026: recent, larger polls weigh more; no institute counts more than once.
Election date
Held on
Results
100% reporting ·
| Candidate | Votes | Share | |
|---|---|---|---|
| Mike RoundsWinnerRepublican Party | 184,589 | 60.5% | |
| Brian BengsIndependent | 120,509 | 39.5% |
| County | Leader | Lead | Votes |
|---|---|---|---|
| Minnehaha | Rounds | +3.1 | 66,634 |
| Pennington | Rounds | +14.3 | 38,216 |
| Lincoln | Rounds | +17.2 | 26,253 |
| Brown | Rounds | +21.2 | 12,011 |
| Brookings | Rounds | +12.0 | 11,441 |
| Lawrence | Rounds | +19.0 | 10,856 |
| Meade | Rounds | +38.3 | 10,001 |
| Codington | Rounds | +30.1 | 9,873 |
| Yankton | Rounds | +17.1 | 7,685 |
| Hughes | Rounds | +32.2 | 6,454 |
All 66 counties
| County | Leader | Lead | Votes |
|---|---|---|---|
| Davison | Rounds | +32.9 | 6,041 |
| Union | Rounds | +34.0 | 5,764 |
| Beadle | Rounds | +36.8 | 4,800 |
| Custer | Rounds | +35.3 | 4,656 |
| Lake | Rounds | +27.9 | 4,426 |
| Clay | Bengs | +12.5 | 4,048 |
| Butte | Rounds | +47.1 | 3,432 |
| Fall River | Rounds | +35.7 | 3,268 |
| Turner | Rounds | +44.6 | 3,242 |
| Roberts | Rounds | +17.0 | 2,957 |
| Grant | Rounds | +40.8 | 2,901 |
| Charles Mix | Rounds | +38.2 | 2,659 |
| Hutchinson | Rounds | +53.2 | 2,555 |
| Moody | Rounds | +23.8 | 2,450 |
| Spink | Rounds | +36.4 | 2,257 |
| Day | Rounds | +23.7 | 2,245 |
| Hamlin | Rounds | +48.6 | 2,231 |
| McCook | Rounds | +43.8 | 2,162 |
| Oglala Lakota | Bengs | +68.7 | 2,150 |
| Bon Homme | Rounds | +43.6 | 2,145 |
| Kingsbury | Rounds | +38.6 | 2,051 |
| Tripp | Rounds | +59.4 | 1,933 |
| Brule | Rounds | +36.8 | 1,771 |
| Deuel | Rounds | +40.7 | 1,687 |
| Marshall | Rounds | +21.7 | 1,655 |
| Walworth | Rounds | +55.1 | 1,640 |
| Todd | Bengs | +49.7 | 1,606 |
| Gregory | Rounds | +51.0 | 1,571 |
| Clark | Rounds | +52.6 | 1,533 |
| Edmunds | Rounds | +51.1 | 1,440 |
| Stanley | Rounds | +48.1 | 1,325 |
| Hand | Rounds | +56.1 | 1,267 |
| Perkins | Rounds | +55.7 | 1,265 |
| Douglas | Rounds | +72.2 | 1,259 |
| Dewey | Bengs | +7.7 | 1,254 |
| Hanson | Rounds | +50.2 | 1,181 |
| Lyman | Rounds | +29.6 | 1,125 |
| McPherson | Rounds | +64.5 | 992 |
| Aurora | Rounds | +40.3 | 968 |
| Potter | Rounds | +61.3 | 924 |
| Miner | Rounds | +40.7 | 884 |
| Haakon | Rounds | +70.1 | 836 |
| Bennett | Rounds | +20.0 | 833 |
| Sanborn | Rounds | +41.5 | 827 |
| Faulk | Rounds | +61.5 | 815 |
| Jackson | Rounds | +32.3 | 771 |
| Sully | Rounds | +61.5 | 712 |
| Corson | Rounds | +11.3 | 710 |
| Jerauld | Rounds | +40.9 | 694 |
| Harding | Rounds | +72.6 | 657 |
| Mellette | Rounds | +22.8 | 606 |
| Campbell | Rounds | +62.4 | 601 |
| Ziebach | Rounds | +5.8 | 567 |
| Hyde | Rounds | +56.9 | 506 |
| Jones | Rounds | +67.0 | 455 |
| Buffalo | Bengs | +22.0 | 364 |
How the count progressed
Updated
Polls vs result
The last polling average before the vote () against the actual result.
- Mean absolute error
- 5.3 pts
- Error on the winner’s margin
- −10.6 pts
| Candidate | Average | Result | Error |
|---|---|---|---|
| Rounds (R) | 50.7% | 60.5% | −9.8 |
| Bengs (I) | 40.3% | 39.5% | +0.8 |
Error = average − result, in percentage points. A dash means the party or candidate was missing from the average or the result; it is left out of both errors.
Polling trend
The average of recent polls. Newer polls and more accurate pollsters count more. How it’s calculated
Latest polls
Each poll as published, with its pollster, fieldwork dates, sample size and a link to the source.
How to read a poll
- Sample size is how many people were asked. More people means less random error, never none.
- ±3 is the margin of error: the real figure is likely within 3 points either way of the one shown.
- Two polls can differ because they were taken on different dates, with different methods and different samples.
- est. means the institute did not publish a margin of error, so it is estimated from the sample size.
- The average smooths this out: it combines recent polls, so one unusual poll cannot swing the picture.
What the polls say
Rounds (R) leads the polling average in South Dakota on 50.7%, 10.4 points ahead of Bengs (I) (40.3%). The biggest shift over the past month is Rounds (R), up 5.8 points.
8 polls from 7 institutes were published in the last 30 days of polling. The most recent is from Concord Public Opinion Partners (D), published 26 Oct 2026. The average gives recent and larger polls more weight and counts no institute more than once; read how it works.
Candidates
Who is standing, in order of the polling average, then the result.
- Mike RoundsRepublican
- Brian Bengs
Forecast
All 2026 racesHow likely each side is to win, according to the main forecasters.
Safe RForecast
Chance of winning: Mike Rounds (R) 95%, Brian Bengs (I) 5%
- Cook Political ReportSafe R
- Sabato's Crystal BallSafe R
- Inside ElectionsSafe R
- Split TicketLikely R
How the forecast has moved
Model
Chance of winning by party, one point per daily snapshot.
Show all 7 forecasters
FiftyPlusOne
CM Election Predictions
America First Insight
OpenSourceZone
Kalshi
Polymarket
PredictIt
Rating changes
- PredictIt:Likely RSafe R3 Nov
- Split Ticket:Safe RLikely R3 Nov
- PredictIt:Safe RLikely R28 Oct
- Split Ticket:Likely RSafe R28 Oct
- VoteHub:Likely RSafe R28 Oct
- CM Election Predictions:Likely RSafe R21 Oct
- FiftyPlusOne:Likely RSafe R21 Oct
- CM Election Predictions:Safe RLikely R20 Oct
- FiftyPlusOne:Safe RLikely R20 Oct
- VoteHub:Safe RLikely R20 Oct
- Kalshi:Likely RSafe R4 Oct
Government
Who governs South Dakota now.
Larry Rhoden
Governor of South Dakota