South Dakota Senate 2026

Name: 2026 South Dakota U.S. Senate election
Start: 2026-11-03
End: 2026-11-03
Location: South Dakota

Mike Rounds (R) · running · Cook PVI R+15 · last result 65.74% R

Safe RShare card

Independent

Brian Bengs

7¢

Polymarket price

Republican

Mike Rounds

92¢

Polymarket price

Wikipedia bio

Marion Michael Rounds is an American businessman and politician serving as the junior United States senator from South Dakota since 2015. A member of the Republican Party, he served as the 31st governor of South Dakota from 2003 to 2011.

Source: Mike Rounds

Polymarket · Mike Rounds (R) · 92¢. The contract price, not a forecast model.

Desk notes

Generated from the sourced figures on this page. Not a separate report.

Mike Rounds (R) is the incumbent, running. The ratings consensus is Safe R. Cook’s cell is dated Oct 6, 2026. 10 forecaster cells are stored. Kalshi Mike Rounds 92¢ (mid). Polymarket Mike Rounds 92¢ (mid). The 2024 presidential margin in this state was R+29.2. The 2020 presidential margin in this state was R+26.2.

Polling average

No polling average for this race. That is an empty state, not a tie.

Ratings

Cook Political ReportOct 6, 2026Solid R
Sabato's Crystal BallOct 14, 2026Safe R
Inside ElectionsOct 15, 2026Solid R
Decision Desk HQOct 19, 2026Safe R
RealClearPoliticsOct 12, 2026Solid R
Silver BulletinOct 19, 2026Solid R
FiftyPlusOneOct 19, 2026Likely R
The EconomistOct 19, 2026Likely R
Fox NewsOct 13, 2026Solid R
Split TicketOct 19, 2026Likely R

Quoted from the Wikipedia predictions table, not scraped from the raters.

Markets

Raw yes-prices. Not vig-adjusted. Contracts under 1¢ are omitted.

KalshiKalshiOct 20, 10:14 AM EDT

Mike Rounds92¢mid · spread 1¢
Brian Bengs8¢mid · spread 1¢

PolymarketPolymarketOct 20, 10:14 AM EDT

Mike Rounds (R)92¢mid · spread 1¢
Brian Bengs (I)7¢mid · spread 1¢

PredictIt is off. Its terms limit the feed to non-commercial use.

Price history

through Oct 20, 9:44 AM EDT

WindowSep 20, 10:00 AM EDT

KalshiMike Rounds 92¢ at Oct 20, 9:44 AM EDT· Kalshi public candlesticks · 121 hours

PolymarketMike Rounds 92¢ at Oct 20, 9:44 AM EDT· Polymarket CLOB prices-history · 693 hours

KalshiBrian Bengs 8¢ at Oct 20, 9:44 AM EDT· hourly pull · 21 hours

PolymarketBrian Bengs 7¢ at Oct 20, 9:44 AM EDT· hourly pull · 21 hours

Marker Oct 5, 8:00 PM EDT · Rating dated Oct 6, 2026

Marker Oct 18, 8:00 PM EDT · Rating dated Oct 19, 2026

Marker Oct 12, 8:00 PM EDT · Rating dated Oct 13, 2026

Marker Oct 14, 8:00 PM EDT · Rating dated Oct 15, 2026

Marker Oct 11, 8:00 PM EDT · Rating dated Oct 12, 2026

Marker Oct 13, 8:00 PM EDT · Rating dated Oct 14, 2026

Scale is fixed at 0–100¢. Hourly closes. A dashed line is a rating date or a poll end date stored on this race. Times are US Eastern.

Money

No FEC snapshot for this race.

Recent polls

No individual polls in this snapshot.

What changed

market
South Dakota Senate: the stored prices were compared and no contract moved by a full cent.

Results

Results appear here once official returns start on election night, November 3, 2026.

Counts will come from civicAPI, which compiles official state election offices. A winner is shown only when civicAPI projects one, labelled as such.

Official results: South Dakota election office ↗

Updated Oct 20, 10:10 AM EDT · snapshot Oct 20, 10:10 AM EDT · mode live