**Republican Senate incumbents facing primary challenges in 2026 have produced a trader consensus favoring exactly three losses at 73.8 percent.** Confirmed defeats include John Cornyn in Texas, where Attorney General Ken Paxton secured the nomination, and Bill Cassidy in Louisiana amid a competitive field that included Rep. Julia Letlow. These outcomes align with patterns of intra-party opposition in open or vulnerable seats. Additional factors include Joni Ernst’s decision not to seek re-election in Iowa and the vacancy created by Lindsey Graham’s death in South Carolina, which triggered a special primary. With several primaries recently concluded or still pending, the elevated number of losses relative to historical averages has anchored expectations around three, while lower probabilities for two or four reflect uncertainty over any remaining contested races.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated3 73.8%
4 12.1%
2 8.2%
>4 7.9%
$54,101 Vol.
$54,101 Vol.
0
<1%
1
1%
2
8%
3
74%
4
12%
>4
6%
3 73.8%
4 12.1%
2 8.2%
>4 7.9%
$54,101 Vol.
$54,101 Vol.
0
<1%
1
1%
2
8%
3
74%
4
12%
>4
6%
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.
Market Opened: Jan 14, 2026, 2:51 PM ET
Resolver
0x2F5e3684c...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.
Resolver
0x2F5e3684c...**Republican Senate incumbents facing primary challenges in 2026 have produced a trader consensus favoring exactly three losses at 73.8 percent.** Confirmed defeats include John Cornyn in Texas, where Attorney General Ken Paxton secured the nomination, and Bill Cassidy in Louisiana amid a competitive field that included Rep. Julia Letlow. These outcomes align with patterns of intra-party opposition in open or vulnerable seats. Additional factors include Joni Ernst’s decision not to seek re-election in Iowa and the vacancy created by Lindsey Graham’s death in South Carolina, which triggered a special primary. With several primaries recently concluded or still pending, the elevated number of losses relative to historical averages has anchored expectations around three, while lower probabilities for two or four reflect uncertainty over any remaining contested races.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated


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