U.S. Senate
RMike Rounds
51.2%
average of 4 polls
IBrian Bengs
39.8%
average of 4 polls
Difference: 11.4 points
Photos: Mike Rounds, Office of Governor Mike Rounds, Public domain. Candidates without a freely licensed photo are shown by initials.
The leading candidates are not a Democrat and a Republican, so there is no D−R average.
| Pollster | Fieldwork | Sample | Result | Margin |
|---|---|---|---|---|
| Emerson College for KELOLAND | 2026-10-19 to 2026-10-20 | 803 LV | Mike Rounds (R) 50; Brian Bengs (I) 42; Undecided (UND) 8 | — |
| Quantus Insights(R-aligned) | 2026-10-17 to 2026-10-19 | 633 LV | Mike Rounds (R) 57; Brian Bengs (I) 37; Other (OTH) 2; Undecided (UND) 5 | — |
| Mason-Dixon for South Dakota News Watch, Chiesman Center for Democracy at the University of South Dakota | 2026-10-12 to 2026-10-14 | 500 LV | Mike Rounds (R) 56; Brian Bengs (I) 37; Undecided (UND) 7 | — |
| Concord Public Opinion Partners(D-aligned) | 2026-10-06 to 2026-10-08 | 400 LV | Mike Rounds (R) 42; Brian Bengs (I) 43; Other (OTH) 5; Undecided (UND) 10 | — |