← 2026 Senate map · Likely R
South Dakota Senate polls
Bengs (I) vs. Rounds (R)
Mike Rounds leads the 2026 South Dakota Senate race by 4.4 points in PolitiKool's polling average, as of Oct. 11, 2026.
- Bengs 44.9%, Rounds 49.3%.
- 5 polls from 5 pollsters, weighted by recency, sample size, pollster record and partisan sponsorship.
- The margin has moved 1.0 points toward Mike Rounds over the past month.
- Rated Likely R, combining the average with the Cook Political Report, Sabato's Crystal Ball and Inside Elections.
- The seat is held by Mike Rounds (R).
South Dakota Senate polling average
Brian Bengs44.9%
Mike Rounds49.3%
MarginRounds +4.4
Average as of Oct. 11, 2026 · — Brian Bengs · — Mike Rounds
Latest South Dakota Senate polls
| Dates | Pollster | Sample | Bengs | Rounds | Margin |
|---|---|---|---|---|---|
| Sept. 24–27 | Zenith Research | 500 LV | 47% | 53% | Rounds +6 |
| Sept. 8–9 | Public Policy Polling (partisan) | 629 RV | 42% | 45% | Rounds +3 |
| Aug. 26–30 | Lake Research Partners (partisan) | 500 LV | 51% | 44% | Bengs +7 |
| Aug. 13–17 | Impact Research (partisan) | 500 LV | 44% | 44% | Even |
| July 6–9 | Public Opinion Strategies (partisan) | 500 LV | 33% | 56% | Rounds +23 |
| May 29–30 | Public Policy Polling (partisan) | 726 RV | 40% | 44% | Rounds +4 |
| Feb. 17–18 | Public Policy Polling (partisan) | 685 RV | 35% | 47% | Rounds +12 |
| Nov. 13–14 | Public Policy Polling (partisan) | 814 RV | 31% | 44% | Rounds +13 |
| July 30–31 | Public Policy Polling (partisan) | 524 LV | 28% | 41% | Rounds +13 |