Skip to main content
icon for South Dakota Senate Election Winner
Elections·US Election

South Dakota Senate Election Winner

icon for South Dakota Senate Election Winner
Elections·US Election

South Dakota Senate Election Winner

Mike Rounds (R) 95.5%

Brian Bengs (I) <1%

Democrat <1%

Polymarket

$23,231 Vol.

Mike Rounds (R) 95.5%

Brian Bengs (I) <1%

Democrat <1%

Polymarket

$23,231 Vol.

icon for Mike Rounds (R)

Mike Rounds (R)

$11,231 Vol.

96%

icon for Brian Bengs (I)

Brian Bengs (I)

$612 Vol.

1%

icon for Democrat

Democrat

$11,387 Vol.

1%

This market will resolve according to the winner of the 2026 midterm South Dakota U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.Incumbent Republican Mike Rounds holds a commanding lead in the 2026 South Dakota Senate race due to the state's consistent Republican dominance, demonstrated by strong margins in recent presidential and Senate contests, combined with his decisive primary victory and substantial fundraising advantage. The Democratic nominee's withdrawal in early August left independent Brian Bengs, who previously lost by a wide margin in 2022, as the primary challenger. Election forecasters rate the contest as safe or solid Republican. Trader consensus reflects these structural factors and limited opposition. Late developments such as a significant scandal, health event, or unexpected national political shift could still alter the outcome before the November 3 general election.

This market will resolve according to the winner of the 2026 midterm South Dakota U.S. Senate election, inclusive of any run-offs.

A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.

Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.

The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Volume
$23,231
End Date
Nov 3, 2026
Market Opened
Oct 13, 2025, 5:04 PM ET

Resolver

0x2F5e3684c...
This market will resolve according to the winner of the 2026 midterm South Dakota U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
This market will resolve according to the winner of the 2026 midterm South Dakota U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.Incumbent Republican Mike Rounds holds a commanding lead in the 2026 South Dakota Senate race due to the state's consistent Republican dominance, demonstrated by strong margins in recent presidential and Senate contests, combined with his decisive primary victory and substantial fundraising advantage. The Democratic nominee's withdrawal in early August left independent Brian Bengs, who previously lost by a wide margin in 2022, as the primary challenger. Election forecasters rate the contest as safe or solid Republican. Trader consensus reflects these structural factors and limited opposition. Late developments such as a significant scandal, health event, or unexpected national political shift could still alter the outcome before the November 3 general election.

This market will resolve according to the winner of the 2026 midterm South Dakota U.S. Senate election, inclusive of any run-offs.

A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.

Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.

The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Volume
$23,231
End Date
Nov 3, 2026
Market Opened
Oct 13, 2025, 5:04 PM ET

Resolver

0x2F5e3684c...
This market will resolve according to the winner of the 2026 midterm South Dakota U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.

Related

icon for Will the Republicans win the South Carolina Senate race in 2026?

Will the Republicans win the South Carolina Senate race in 2026?

86%
icon for Will the Republicans win the Nebraska Senate race in 2026?

Will the Republicans win the Nebraska Senate race in 2026?

70%
icon for Will the Democrats win the Minnesota Senate race in 2026?

Will the Democrats win the Minnesota Senate race in 2026?

91%

Beware of external links.

Frequently Asked Questions

"South Dakota Senate Election Winner" is a prediction market on Polymarket with 3 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "Mike Rounds (R)" at 96%, followed by "Brian Bengs (I)" at 1%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 96¢ implies that the market collectively assigns a 96% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

As of today, "South Dakota Senate Election Winner" has generated $23.2K in total trading volume since the market launched on Oct 13, 2025. This level of trading activity reflects strong engagement from the Polymarket community and helps ensure that the current odds are informed by a deep pool of market participants. You can track live price movements and trade on any outcome directly on this page.

To trade on "South Dakota Senate Election Winner," browse the 3 available outcomes listed on this page. Each outcome displays a current price representing the market's implied probability. To take a position, select the outcome you believe is most likely, choose "Yes" to trade in favor of it or "No" to trade against it, enter your amount, and click "Trade." If your chosen outcome is correct when the market resolves, your "Yes" shares pay out $1 each. If it's incorrect, they pay out $0. You can also sell your shares at any time before resolution if you want to lock in a profit or cut a loss.

The current frontrunner for "South Dakota Senate Election Winner" is "Mike Rounds (R)" at 96%, meaning the market assigns a 96% chance to that outcome. The next closest outcome is "Brian Bengs (I)" at 1%. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "South Dakota Senate Election Winner" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.