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How many Republican Senate Incumbents will not win their Primary?
polymarket

How many Republican Senate Incumbents will not win their Primary?

Volume:
$79,391

3

 - Polymarket

3 - Polymarket

1W

News

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Vol.

·

Resolved Sep 16, 2026

Closed: Sep 16, 3:54 AM EST

polymarket

Polymarket

View
Outcome
Trade
Chance %
Price
Spread
Liquidity
Volume
24h
7d
Open Interest
Ends in
Result
polymarket

3

View
100%
Yes 100¢No 0¢
0.1¢
N/A
$20,101
N/A
N/A
N/A
N/A
Yes
polymarket

2

View
0%
3%
Yes 0¢No 100¢
—
N/A
$39,772
N/A
N/A
N/A
N/A
No
polymarket

4

View
0%
Yes 0¢No 100¢
—
N/A
$6,880
N/A
N/A
N/A
N/A
No
polymarket

1

View
0%
Yes 0¢No 100¢
—
N/A
$4,323
N/A
N/A
N/A
N/A
No
polymarket

0

View
0%
Yes 0¢No 100¢
—
N/A
$4,221
N/A
N/A
N/A
N/A
No
polymarket

>4

View
0%
Yes 0¢No 100¢
—
N/A
$4,094
N/A
N/A
N/A
N/A
No
Total markets: 6

Description

The 2026 midterm elections are scheduled to be held on November 3, 2026, with congressional primaries running from March through September. This market will resolve according to the number of Republican Senate incumbents who do not win their nominating election to move on to the general election as a result of the 2026 midterm primary elections. An incumbent will be considered not to have won their election if they are not declared the winner of the election they sought, including if they withdraw, suspend, or otherwise leave the race at any point after officially registering as a candidate, regardless of the reason. Incumbents who do not officially register as candidates for reelection will not be considered. This market will resolve based on the results of all Senate nominating elections, including party primaries, top-two or jungle primaries, and primaries for special elections, that are scheduled to occur between March 1 and September 30, 2026. If a required runoff for any such election or a subsequent qualifying round in a non-partisan primary system could change the market’s outcome, the market will remain open until that contest is conclusively called by this market’s resolution sources. A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time of their nominating election. A candidate without a ballot-listed affiliation to either the Democratic or Republican parties will be considered a member of one of these parties based on the party with which they most recently expressed their intent to caucus prior to the conclusion of the relevant nominating election. The resolution source for this market will be the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all relevant nominating elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on official state certification of the nominating election results.

Polymarket

The 2026 midterm elections are scheduled to be held on November 3, 2026, with congressional primaries running from March through September. This market will resolve according to the number of Republican Senate incumbents who do not win their nominating election to move on to the general election as a result of the 2026 midterm primary elections. An incumbent will be considered not to have won their election if they are not declared the winner of the election they sought, including if they withdraw, suspend, or otherwise leave the race at any point after officially registering as a candidate, regardless of the reason. Incumbents who do not officially register as candidates for reelection will not be considered. This market will resolve based on the results of all Senate nominating elections, including party primaries, top-two or jungle primaries, and primaries for special elections, that are scheduled to occur between March 1 and September 30, 2026. If a required runoff for any such election or a subsequent qualifying round in a non-partisan primary system could change the market’s outcome, the market will remain open until that contest is conclusively called by this market’s resolution sources. A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time of their nominating election. A candidate without a ballot-listed affiliation to either the Democratic or Republican parties will be considered a member of one of these parties based on the party with which they most recently expressed their intent to caucus prior to the conclusion of the relevant nominating election. The resolution source for this market will be the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all relevant nominating elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on official state certification of the nominating election results.

Frequently asked questions

On Polymarket, the Republican Senate primary upsets market dashboard tracks real-time odds and trading activity for how many Republican Senate incumbents will fail to win their primary elections. The dashboard displays current market prices, historical price movements, and total trading volume of $79,391 across all outcomes. Traders use this venue to forecast primary challenges and incumbent vulnerability heading into the election cycle. The market aggregates collective predictions on a specific numerical outcome, allowing participants to assess consensus expectations about primary contest results among sitting Republican senators.

Prediction market odds and polling averages often diverge because they measure different signals. Polls capture voter sentiment at a single moment, while this market reflects traders' forward-looking assessments of actual primary outcomes, incorporating campaign dynamics, fundraising, and insider expectations. Markets tend to update faster than polls when new information emerges. Comparing the two reveals whether traders expect primary results to differ from current voter preferences, making the market a useful complement to traditional polling for understanding incumbent vulnerability and the likelihood of primary upsets.

On Polymarket, this market is priced through an automated market maker that converts trader buy and sell orders into real-time odds for each outcome. On Polymarket, prices reflect that venue's order book, liquidity, and how traders price the outcome right now. Traders purchase shares representing their prediction of how many Republican Senate incumbents will lose their primary, and the price of each outcome reflects the collective confidence in that scenario. As new information surfaces or sentiment shifts, prices adjust dynamically. The spread between bid and ask prices reflects liquidity and market uncertainty, with tighter spreads indicating higher confidence and deeper participation.

Key catalysts include primary candidate announcements and challenger recruitment, which signal incumbent vulnerability. Fundraising reports and polling within individual states reveal competitive intensity and voter sentiment shifts. Endorsements from party leadership or grassroots movements can reshape primary dynamics. Scandals, legislative votes, or high-profile statements by incumbents may trigger primary challenges. National political events and shifts in party priorities also influence whether sitting senators face credible opposition. Traders monitoring these signals can anticipate market moves before prices fully adjust to new information about primary competitiveness.