Republicans currently hold a 53-seat Senate majority heading into the 2026 midterms, defending 22 of the 35 seats up for election while Democrats protect 13. The closely matched probabilities around 49 to 51 seats reflect the mixed map, where Democrats must net four gains to take control amid competitive contests in Georgia and Michigan, offset by Republican advantages in Trump-won states such as North Carolina and Ohio. Midterm headwinds tied to the administration’s approval ratings and economic sentiment add uncertainty, though historical patterns favor the party holding the White House retaining a narrow edge. Key primaries and fall campaign dynamics in these battlegrounds will likely determine whether Republicans hold steady or see modest shifts by November.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated$2,301,940 Vol.
$2,301,940 Vol.
≤47
26%
48
10%
49
16%
50
18%
51
16%
52
6%
53
3%
54
2%
55
1%
56
1%
57+
4%
$2,301,940 Vol.
$2,301,940 Vol.
≤47
$78,569 Vol.
26%
48
$29,873 Vol.
10%
49
$25,875 Vol.
16%
50
$79,939 Vol.
18%
51
$176,160 Vol.
16%
52
$524,378 Vol.
6%
53
$32,790 Vol.
3%
54
$728,384 Vol.
2%
55
$414,149 Vol.
1%
56
$159,598 Vol.
1%
57+
$52,225 Vol.
4%
The 2026 midterm elections are scheduled to be held on November 3, 2026.
This market will resolve according to the number of seats held by the Republican Party in the US Senate as a result of the 2026 midterm elections.
This market will resolve based on the results of all Senate elections, including special elections, that are scheduled to occur in November 2026 as of October 31, 2026. If a required runoff for any such election could change the market’s outcome, the market will remain open until that runoff is conclusively called by this market’s resolution sources.
If a Senate seat is vacant but a corresponding election is not held in November 2026, the seat will be considered held by the party of the seat's most recent incumbent.
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 Senate elections are conclusively called by this market's resolution sources. 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 at the time all of the Senate elections are conclusively called by this market's resolution sources.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all Senate elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on the official certification.Republicans currently hold a 53-seat Senate majority heading into the 2026 midterms, defending 22 of the 35 seats up for election while Democrats protect 13. The closely matched probabilities around 49 to 51 seats reflect the mixed map, where Democrats must net four gains to take control amid competitive contests in Georgia and Michigan, offset by Republican advantages in Trump-won states such as North Carolina and Ohio. Midterm headwinds tied to the administration’s approval ratings and economic sentiment add uncertainty, though historical patterns favor the party holding the White House retaining a narrow edge. Key primaries and fall campaign dynamics in these battlegrounds will likely determine whether Republicans hold steady or see modest shifts by November.
The 2026 midterm elections are scheduled to be held on November 3, 2026.
This market will resolve according to the number of seats held by the Republican Party in the US Senate as a result of the 2026 midterm elections.
This market will resolve based on the results of all Senate elections, including special elections, that are scheduled to occur in November 2026 as of October 31, 2026. If a required runoff for any such election could change the market’s outcome, the market will remain open until that runoff is conclusively called by this market’s resolution sources.
If a Senate seat is vacant but a corresponding election is not held in November 2026, the seat will be considered held by the party of the seat's most recent incumbent.
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 Senate elections are conclusively called by this market's resolution sources. 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 at the time all of the Senate elections are conclusively called by this market's resolution sources.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all Senate elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on the official certification.
This market will resolve according to the number of seats held by the Republican Party in the US Senate as a result of the 2026 midterm elections.
This market will resolve based on the results of all Senate elections, including special elections, that are scheduled to occur in November 2026 as of October 31, 2026. If a required runoff for any such election could change the market’s outcome, the market will remain open until that runoff is conclusively called by this market’s resolution sources.
If a Senate seat is vacant but a corresponding election is not held in November 2026, the seat will be considered held by the party of the seat's most recent incumbent.
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 Senate elections are conclusively called by this market's resolution sources. 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 at the time all of the Senate elections are conclusively called by this market's resolution sources.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all Senate elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on the official certification.
Market Opened: Dec 18, 2025, 8:55 PM ET
Volume
$2,301,940Market Opened
Dec 18, 2025, 8:55 PM ETResolver
0x2F5e3684c...The 2026 midterm elections are scheduled to be held on November 3, 2026.
This market will resolve according to the number of seats held by the Republican Party in the US Senate as a result of the 2026 midterm elections.
This market will resolve based on the results of all Senate elections, including special elections, that are scheduled to occur in November 2026 as of October 31, 2026. If a required runoff for any such election could change the market’s outcome, the market will remain open until that runoff is conclusively called by this market’s resolution sources.
If a Senate seat is vacant but a corresponding election is not held in November 2026, the seat will be considered held by the party of the seat's most recent incumbent.
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 Senate elections are conclusively called by this market's resolution sources. 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 at the time all of the Senate elections are conclusively called by this market's resolution sources.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all Senate elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on the official certification.Republicans currently hold a 53-seat Senate majority heading into the 2026 midterms, defending 22 of the 35 seats up for election while Democrats protect 13. The closely matched probabilities around 49 to 51 seats reflect the mixed map, where Democrats must net four gains to take control amid competitive contests in Georgia and Michigan, offset by Republican advantages in Trump-won states such as North Carolina and Ohio. Midterm headwinds tied to the administration’s approval ratings and economic sentiment add uncertainty, though historical patterns favor the party holding the White House retaining a narrow edge. Key primaries and fall campaign dynamics in these battlegrounds will likely determine whether Republicans hold steady or see modest shifts by November.
The 2026 midterm elections are scheduled to be held on November 3, 2026.
This market will resolve according to the number of seats held by the Republican Party in the US Senate as a result of the 2026 midterm elections.
This market will resolve based on the results of all Senate elections, including special elections, that are scheduled to occur in November 2026 as of October 31, 2026. If a required runoff for any such election could change the market’s outcome, the market will remain open until that runoff is conclusively called by this market’s resolution sources.
If a Senate seat is vacant but a corresponding election is not held in November 2026, the seat will be considered held by the party of the seat's most recent incumbent.
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 Senate elections are conclusively called by this market's resolution sources. 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 at the time all of the Senate elections are conclusively called by this market's resolution sources.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all Senate elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on the official certification.
This market will resolve according to the number of seats held by the Republican Party in the US Senate as a result of the 2026 midterm elections.
This market will resolve based on the results of all Senate elections, including special elections, that are scheduled to occur in November 2026 as of October 31, 2026. If a required runoff for any such election could change the market’s outcome, the market will remain open until that runoff is conclusively called by this market’s resolution sources.
If a Senate seat is vacant but a corresponding election is not held in November 2026, the seat will be considered held by the party of the seat's most recent incumbent.
A candidate's party will be determined by their ballot-listed or otherwise identifiable affiliation with that party at the time all of the 2026 Senate elections are conclusively called by this market's resolution sources. 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 at the time all of the Senate elections are conclusively called by this market's resolution sources.
The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources have conclusively called all Senate elections. If all three sources do not achieve consensus in calling the relevant races for this market, it will resolve based on the official certification.
Volume
$2,301,940Market Opened
Dec 18, 2025, 8:55 PM ETResolver
0x2F5e3684c...Republicans currently hold a 53-seat Senate majority heading into the 2026 midterms, defending 22 of the 35 seats up for election while Democrats protect 13. The closely matched probabilities around 49 to 51 seats reflect the mixed map, where Democrats must net four gains to take control amid competitive contests in Georgia and Michigan, offset by Republican advantages in Trump-won states such as North Carolina and Ohio. Midterm headwinds tied to the administration’s approval ratings and economic sentiment add uncertainty, though historical patterns favor the party holding the White House retaining a narrow edge. Key primaries and fall campaign dynamics in these battlegrounds will likely determine whether Republicans hold steady or see modest shifts by November.
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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