South Dakota Senate Election Results 2026: Rounds vs Bengs

Result

Complete

DDHQ projects Mike Rounds (R), 10:03 pm ET

Mike Rounds R60.5%

184,589 votes

Brian Bengs I39.5%

120,513 votes

671 of 671 precincts reporting. South Dakota Secretary of State, Nov 9, 2:07 am ET (7:07 am 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

South Dakota Senate 2026 results: Mike Rounds (R) vs Brian Bengs (I)

Complete

South Dakota senate polling average

17 general election polls