Independent
Brian Bengs
Major-party general-election nominee.
← all Senate races
South Dakota U.S. Senate election, 2026
Brian Bengs (I) vs. Mike Rounds (R). Incumbent re-elected.
No Democrat on the ballot — the race is Bengs (I) vs. Rounds (R)
Democratic nominee Julian Beaudion ended his campaign after the June primary. The November contest is Republican Mike Rounds against independent Brian Bengs, a matchup this Democratic-versus-Republican model does not forecast.
Independent-vs-Republican forecast
Rounds (R) 88% to win
Brian Bengs (I) 12%Mike Rounds (R) 88%
4 polls average Rounds +10.4; a typical miss is ±9 points. A separate independent-vs-Republican method, not the main model: the recency-weighted poll average, with a spread set by how far polls missed in past competitive independent Senate races (Kansas 2014, Utah 2022; both overstated the independent). It is not part of the Senate-control figure, where this seat counts for the party defending it.
The main model publishes no number for this race. It forecasts a Democrat against a Republican, so the figure above comes from the separate independent-vs-Republican method.
Republican
Mike Rounds
Incumbent. Voting record and biography →
Polls
The polls behind it
2 polls · newest firstEach pollster name links to the poll's source; the grade under it is its VotePredictor grade from past elections. Margin is the poll as published. The ± under the sample size is the 95% margin of error on each candidate's share, from the sample size (the gap between them is about twice as uncertain). VotePredictor adjusted (“Our adj.” on small screens) is not a poll: it is our correction of that poll, for its pollster's record in past elections and for registered-voter or all-adult samples. It is the number our forecast reads.
PollsterDateSampleMarginOur adj.VotePredictor adjusted
Campaign money
FEC reports through October 14, 2026Mike RoundsREP · incumbent$5.1M raised
Spent $5.5MCash on hand $1.3M2% from donors under $200
Top contributors, industries and states
Contributors
Industries
- Finance, Insurance & Real Estate$231k
- Technology & Communications$169k
- Retired$143k
- Self-Employed & Freelance$95k
- Legal & Professional Services$87k
States
- CA$384k
- SD$175k
- NY$142k
- VA$136k
- TX$126k
Brian BengsIND$1.9M raised
Spent $1.8MCash on hand $70k47% from donors under $200
Top contributors, industries and states
Contributors
Industries
- Unemployed$466k
- Self-Employed & Freelance$100k
- Finance, Insurance & Real Estate$25k
- Legal & Professional Services$14k
- Technology & Communications$11k
States
- SD$192k
- CA$98k
- MD$53k
- NY$50k
- MA$41k
What each candidate's own campaign committees reported for the 2025–26 cycle; outside spending by PACs and parties is not included. Industries are classified from donors' reported employers. The Senate forecast does not read these figures. Data: GovMoneyGraph, based on FEC records.
Other forecasts
Cook
Solid R≈ R 99%
as of Nov 2, 2026
DDHQ
Safe R≈ R 99%
as of Nov 3, 2026
Econ
Safe R≈ R 99%
as of Nov 3, 2026
FPO
Safe R≈ R 99%
as of Nov 2, 2026
Fox
Solid R≈ R 99%
as of Nov 1, 2026
IE
Solid R≈ R 99%
as of Oct 29, 2026
MS NOW
Safe R≈ R 99%
as of Oct 29, 2026
NBC
Solid R≈ R 99%
as of Nov 3, 2026
RCP
Solid R≈ R 99%
as of Nov 2, 2026
Sabato
Safe R≈ R 99%
as of Nov 2, 2026
Silver
Solid R≈ R 99%
as of Nov 3, 2026
ST
Likely R≈ R 90%
as of Nov 2, 2026
The source we collect records each outlet's rating category, not a probability; some of these outlets run models with their own numbers on their sites. The ≈ figure is the standard conversion of the category (Toss-up 50%, Tilt 60%, Lean 75%, Likely 90%, Solid 99%), the one our scorecard grades them on, not a number they published. They remain independent of VotePredictor. Sources and update dates ↗
Past results
Every U.S. Senate election in South Dakota we hold a result for. A state elects two senators on separate cycles, so this covers both of its seats, not only the one on the ballot in 2026.
YearWinnerMargin
Candidate news
Daylight saving time: When do clocks 'fall back' an hour?
Daylight saving time will end this weekend as scheduled, bringing sunsets before 5 p.m. to some cities. At 2 a.m. Sunday, clocks in 48 states will fall back one hour, giving back the hour taken in springtime .The change will give many an extra hour in bed an…
Yahoo Entertainment · October 29, 2026
I'm independent Brian Bengs. This is why I want South Dakota's vote for Senate
A retired military prosecutor challenges Mike Rounds for Senate, citing lobbyist ties, private jet spending, and pushing term limits in Congress.
Fox News · October 22, 2026
Poll shows big lead for South Dakota Republican Rounds
Republican Sen. Mike Rounds of South Dakota leads in his Senate race by more than 20 points, according to a new poll shared first with Semafor, a sign that any blue wave in November will have its limits. Rounds is trouncing independent candidate Brian Bengs 5…
Biztoc.com · October 21, 2026
Conservatives demand competition — except in their own primaries
Conservatives say they believe in competition. So why on earth do we tolerate a political system in which one man effectively picks our candidates before voters have a chance to examine them?Friedrich Hayek understood why monopoly is dangerous: “Our freedom o…
TheBlaze · October 21, 2026
Ranchers Say Trump’s Beef Imports Have GOP Senator Mike Rounds ‘Treading Water’ In South Dakota
President Donald Trump’s imports of foreign beef has become a major campaign issue for Republican South Dakota Sen. Mike Rounds.
The Daily Caller · October 19, 2026