South Dakota Senate
Tue, Nov 3 · Seat held by Mike Rounds Republican since Jan 2015
Brian L Bengs 39.6Mike Rounds 51.1
Average of 4 polls, Oct 12 to Oct 26, from VoteHub · how it’s calculated
Newest poll
1 is a partisan pollNewest · Concord Public Opinion Partners, field dates Oct 22 to Oct 26, released Oct 30, 448 likely voters, partisan (D), per VoteHubPoll sponsored by Democrats for Education ReformPolls fetched Oct 30, 2:02 a.m. ET, from VoteHub
Polls over time
4 polls, through Election Day Nov 3The thick line is the 7-week average, not a forecast. How it’s calculated. All polls. Polls fetched Oct 30, 2:02 a.m. ET, from VoteHub.
The polls in this chart (4)
4 polls released in the last 14 days · latest results range from 41 to 57.2% (R) and 36.5 to 43% (I) (newest 4 polls on the chart)
4 of the 4 polls for this race, each with both names, plotted on the field end date.
| Pollster | Field dates | Released | Sample | Rounds | Bengs |
|---|---|---|---|---|---|
| Concord Public Opinion Partners | Oct 22 to Oct 26 | Oct 30 | 448 likely voters | 41 | 43 |
| Emerson College | Oct 19 to Oct 21 | Oct 22 | 803 likely voters | 50 | 42 |
| Quantus Insights | Oct 17 to Oct 19 | Oct 22 | 657 likely voters | 57.2 | 36.5 |
| Mason-Dixon | Oct 12 to Oct 14 | Oct 22 | 500 likely voters | 56 | 37 |
Side by side
Left column: BengsRight column: Rounds
- Total receipts, 2025-2026 cycle, through Oct 14
- $1.9M
- $3.8M
- Cash on hand
- $70K
- $1.3M
- Donor-based spectrum
- LiberalCentristConservativeBengsRounds
- Races won and lost
- None on file
- 4-0
- Years since first win on file
- Not available
- 11
- Age on Election Day
- Not available
- 72
Money: FEC bulk data, through Oct 14. One or more are matched to the FEC by name, party and seat, so a total could belong to someone else.
How these are counted
Total receipts line of each candidate’s principal campaign committee, 2025-2026 cycle. Other sites may show career, six-year or all-committee totals, which differ. Bengs: $1,855,763 received, $69,708 cash on hand. Rounds: $3,810,748 received, $1,295,543 cash on hand. The spectrum is a published research score, not our rating. How this works. Wins and losses count the races in our results files, the same as each profile.
What changed in this race
Newest firstNEW POLLSouth Dakota Senate
South Dakota Senate: Brian Bengs 43, Mike Rounds 41
Concord Public Opinion Partners, Oct 22 to Oct 26, 448 likely voters
NEW POLLSouth Dakota Senate
South Dakota Senate: Mike Rounds 50, Brian Bengs 42
Emerson College, Oct 19 to Oct 20, 803 likely voters
More about this race
Candidates on the ballot
- Mike RoundsIncumbentRepublican
- Brian L BengsIndependent
Some names come from filing lists and may not be on the ballot.
Source: vip.sdsos.gov, dated Oct 28
Seat on the ballot, shift from 2014 to 2020: 10.5 points toward Republicans (Republican by 20.9 in 2014, Republican by 31.4 in 2020).
Vote in South Dakota
Trouble voting? Election Protection hotline: 866-OUR-VOTE. A nonpartisan coalition of civil-rights and voting-rights groups, not a government service. 866ourvote.org
Official results for South Dakota
History (16 elections for this seat)
- Votes for listed candidates
- 348,020
- Election day
- November 8, 2022
US Senate, South Dakota, 2022, every candidate Candidate Party Votes and share Share RepublicanJohn ThuneWon Republican 242,31669.6% DemocraticBrian L Bengs Democratic 91,00726.1% LibertarianTamara J Lesnar Libertarian 14,6974.2% - Votes for listed candidates
- 420,219
- Election day
- November 3, 2020
US Senate, South Dakota, 2020, every candidate Candidate Party Votes and share Share RepublicanMike RoundsWon Republican 276,23265.7% DemocraticDan Ahlers Democratic 143,98734.3% - Votes for listed candidates
- 369,656
- Election day
- November 8, 2016
US Senate, South Dakota, 2016, every candidate Candidate Party Votes and share Share RepublicanJohn ThuneWon Republican 265,51671.8% DemocraticJay Williams Democratic 104,14028.2% - Votes for listed candidates
- 279,412
- Election day
- November 4, 2014
US Senate, South Dakota, 2014, every candidate Candidate Party Votes and share Share RepublicanMike RoundsWon Republican 140,74150.4% DemocraticRick Weiland Democratic 82,45629.5% IndependentLarry Pressler Independent 47,74117.1% IndependentGordon Howie Independent 8,4743.0% - Votes for listed candidates
- 227,947
- Election day
- November 2, 2010
US Senate, South Dakota, 2010, every candidate Candidate Party Votes and share Share RepublicanJohn ThuneWon Republican 227,947100.0% - Votes for listed candidates
- 380,673
- Election day
- November 4, 2008
US Senate, South Dakota, 2008, every candidate Candidate Party Votes and share Share DemocraticTim JohnsonWon Democratic 237,88962.5% RepublicanJoel Dykstra Republican 142,78437.5% - Votes for listed candidates
- 391,188
- Election day
- November 2, 2004
US Senate, South Dakota, 2004, every candidate Candidate Party Votes and share Share RepublicanJohn ThuneWon Republican 197,84850.6% DemocraticTom Daschle Democratic 193,34049.4% - Votes for listed candidates
- 337,501
- Election day
- November 5, 2002
US Senate, South Dakota, 2002, every candidate Candidate Party Votes and share Share DemocraticTim JohnsonWon Democratic 167,48149.6% RepublicanJohn Thune Republican 166,94949.5% LibertarianKurt Evans Libertarian 3,0710.9% - Votes for listed candidates
- 262,111
- Election day
- November 3, 1998
US Senate, South Dakota, 1998, every candidate Candidate Party Votes and share Share DemocraticTom DaschleWon Democratic 162,88462.1% RepublicanRon Schmidt Republican 95,43136.4% LibertarianByron Dale Libertarian 3,7961.4% - Votes for listed candidates
- 324,487
- Election day
- November 5, 1996
US Senate, South Dakota, 1996, every candidate Candidate Party Votes and share Share DemocraticTim JohnsonWon Democratic 166,53351.3% RepublicanLarry Pressler Republican 157,95448.7% - Votes for listed candidates
- 334,495
- Election day
- November 3, 1992
US Senate, South Dakota, 1992, every candidate Candidate Party Votes and share Share DemocraticThomas A. DaschleWon Democratic 217,09564.9% RepublicanCharlene Haar Republican 108,73332.5% LibertarianGus Hercules Libertarian 4,3531.3% IndependentKent Hyde Independent 4,3141.3% - Votes for listed candidates
- 258,976
- Election day
- November 6, 1990
US Senate, South Dakota, 1990, every candidate Candidate Party Votes and share Share RepublicanLarry PresslerWon Republican 135,68252.4% DemocraticTed Muenster Democratic 116,72745.1% IndependentDean L. Sinclair Independent 6,5672.5% - Votes for listed candidates
- 295,830
- Election day
- November 4, 1986
US Senate, South Dakota, 1986, every candidate Candidate Party Votes and share Share DemocraticThomas A. DaschleWon Democratic 152,65751.6% RepublicanJames Abdnor Republican 143,17348.4% - Votes for listed candidates
- 315,713
- Election day
- November 6, 1984
US Senate, South Dakota, 1984, every candidate Candidate Party Votes and share Share RepublicanLarry PresslerWon Republican 235,17674.5% DemocraticGeorge V. Cunningham Democratic 80,53725.5% - Votes for listed candidates
- 327,478
- Election day
- November 4, 1980
US Senate, South Dakota, 1980, every candidate Candidate Party Votes and share Share RepublicanJames AbdnorWon Republican 190,59458.2% DemocraticGeorge McGovern Democratic 129,01839.4% IndependentWayne Peterson Independent 7,8662.4% - Votes for listed candidates
- 255,599
- Election day
- November 7, 1978
US Senate, South Dakota, 1978, every candidate Candidate Party Votes and share Share RepublicanLarry PresslerWon Republican 170,83266.8% DemocraticDon Barnett Democratic 84,76733.2%
1978 to 2022: MIT Election Data and Science Lab, U.S. Senate statewide 1976-2024, retrieved Oct 28, 2026. Compiled by MIT Election Data and Science Lab (MEDSL) from official returns; not an official source
Download and cite
Cite this page
Election Wrld. (2026). US Senate in South Dakota, election results. https://www.electionwrld.com/sd/us-senate. Retrieved October 30, 2026.
Sources
Sources: U.S. Senate: senators contact information XML (class per senator) (US government work, public domain), retrieved Oct 28, 2026; MIT Election Data and Science Lab, U.S. Senate statewide 1976-2024 (CC0 1.0), retrieved Oct 28, 2026, compiled by MIT Election Data and Science Lab (MEDSL) from official returns, not an official source; unitedstates/congress-legislators (current) (CC0-1.0), retrieved Oct 28, 2026, compiled by the @unitedstates project volunteers (rosters from official congressional sources) from official returns, not an official source.
DataState data (JSON)Sources: MIT Election Data and Science Lab, U.S. Senate statewide 1976-2024, VoteHub polls (CC BY 4.0), FEC, DIME (ODC-BY), Portraits: unitedstates/images (public domain)Data as of Oct 28, 2026