US / US midterms 2026 / South Dakota Senate
South Dakota senate
South Dakota Senate 2026 results: Mike Rounds (R) vs Brian Bengs (I)
Election day 3 November 2026
Result
Complete
DDHQ projects Mike Rounds (R), 10:03 pm ET
Mike Rounds R60.5%
184,584 votes
Brian Bengs I39.5%
120,502 votes
671 of 671 precincts reporting. South Dakota Secretary of State, 9:19 pm Wed ET (2:19 am Thu UK).
Count over time
Final pre-election PollCheck polling average
Average: Rounds +10.9. Result: Rounds +21.0
Mike Rounds (R)
51.7%
+1.9 in 30 days
Brian Bengs (I)
40.8%
-5.5 in 30 days
Win probability
98%
Rounds - Safe R
- Incumbent
- Mike Rounds (R)
- Status
- Incumbent renominated
- Last result
- 2020: Mike Rounds (R) 65.7%, Dan Ahlers (D) 34.3%
- 2024 president
- R+29.2
- Election day
- 3 November 2026, polls close 8 pm and 9 pm Eastern (1 am and 2 am Wed UK)
Polling trend
South Dakota senate polling average
Every poll
17 general election polls
| Pollster | Fieldwork | Sample | Rounds | Bengs | Spread | vs avg | Source |
|---|---|---|---|---|---|---|---|
| Concord Public Opinion Partners D Leans D+2.4Poll sponsored by Democrats for Education Reform | 22 Oct 2026 - 26 Oct 2026 | 448 LV | 41% | 43% | Bengs +2 | Rounds -12.9 | Pollster |
| Emerson College Leans R+0.2 | 19 Oct 2026 - 20 Oct 2026 | 803 LV | 50% | 42% | Rounds +8 | Rounds -3.4 | Pollster |
| Quantus Insights R Leans R+1.4 | 17 Oct 2026 - 19 Oct 2026 | 633 LV | 59% | 37% | Rounds +22 | Rounds +9.1 | Pollster |
| Quantus Insights R Leans R+1.4Not in average: same survey, another version used | 17 Oct 2026 - 19 Oct 2026 | 633 LV | 57% | 37% | Rounds +20 | Rounds +7.1 | Pollster |
| Public Opinon Strategies R↑ Poll sponsored by Rounds' campaign | 12 Oct 2026 - 16 Oct 2026 | 500 LV | 54% | 37% | Rounds +17 | Rounds +6.0 | Pollster |
| Mason-Dixon Polling & Strategy Leans R+0.9↑ Poll conducted for South Dakota News Watch and the University of South Dakota | 12 Oct 2026 - 14 Oct 2026 | 500 RV | 56% | 37% | Rounds +19 | Rounds +9.5 | Pollster |
| Concord Public Opinion Partners D Leans D+2.4Poll sponsored by Democrats for Education Reform | 6 Oct 2026 - 8 Oct 2026 | 400 LV | 42% | 43% | Bengs +1 | Rounds -3.5 | Pollster |
| Zenith ResearchPoll sponsored by Bengs' campaign | 24 Sep 2026 - 27 Sep 2026 | 500 LV | 53% | 47% | Rounds +6 | Rounds +2.5 | Pollster |
| Zenith ResearchPoll sponsored by Bengs' campaignNot in average: same survey, another version used | 24 Sep 2026 - 27 Sep 2026 | 500 LV | 44% | 38% | Rounds +6 | Rounds +2.5 | Pollster |
| Public Policy Polling D Leans D+0.9↑ Anastácio, Nicholas [@NenoNicolosio] (September 10, 2026). "Another #SDSEN internal poll: A Public Policy Polling survey conducted for Brian Bengs (I) found him and Sen. Mike Rounds (R) within the margin of error" ( Tweet ) . Retrieved September 11, 2026 – via X (formerly Twitter) .; Poll sponsored by Bengs' campaign | 8 Sep 2026 - 9 Sep 2026 | 629 RV | 45% | 42% | Rounds +3 | Rounds +3.5 | Pollster |
| Lake Research Partners D | 26 Aug 2026 - 30 Aug 2026 | 500 LV | 44% | 51% | Bengs +7 | Pollster | |
| Impact Research D Leans D+0.4Poll sponsored by Bengs' campaign | 13 Aug 2026 - 17 Aug 2026 | 500 LV | 44% | 44% | Tie | Pollster | |
| Public Opinion Strategies R Leans R+0.6↑ Poll sponsored by the NRSCNot in average: taken before the primary (28 July) | 6 Jul 2026 - 9 Jul 2026 | 500 LV | 56% | 33% | Rounds +23 | Pollster | |
| Public Policy Polling D Leans D+0.9Poll sponsored by Bengs' campaignNot in average: taken before the primary (28 July) | 29 May 2026 - 30 May 2026 | 726 RV | 44% | 40% | Rounds +4 | Pollster | |
| Public Policy Polling D Leans D+0.9Poll sponsored by Bengs' campaignNot in average: taken before the primary (28 July) | 17 Feb 2026 - 18 Feb 2026 | 685 RV | 47% | 35% | Rounds +12 | Pollster | |
| Public Policy Polling D Leans D+0.9Poll sponsored by Bengs' campaignNot in average: taken before the primary (28 July) | 13 Nov 2025 - 14 Nov 2025 | 814 RV | 44% | 31% | Rounds +13 | Pollster | |
| Public Policy Polling D Leans D+0.9↑ Nicholas Anastácio [@NenoNicolosio] (October 30, 2025). "A little ol' #SDSEN poll from @njhotline: A Public Policy Polling survey conducted for 2022 nominee Brian Bengs (I) found Sen. Mike Rounds (R) ahead of him in a head-to-head race Rounds 41% Bengs 28% Undecided 31% July 30–31; 552 LVs; +/-4.1%" ( Tweet ) . Retrieved December 4, 2025 – via X (formerly Twitter) .; Poll sponsored by Bengs' campaignNot in average: taken before the primary (28 July) | 30 Jul 2025 - 31 Jul 2025 | 524 LV | 41% | 28% | Rounds +13 | Pollster |
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Poll list adapted from Wikipedia (CC BY-SA 4.0).