Will the Republican Party hold exactly 45 Senate seats after the 2026 midterm elections?
Odds, price jumps explained, and what could move it next
Yes at 18% on 4 Nov 2026, up 12 pts over the previous 7 days. 4 big jumps since 23 Oct 2026, listed below.
Data from Polymarket. Numbered dots are the jumps explained below.
Context
This prediction market asks whether the Republican Party will hold exactly 45 seats in the United States Senate following the November 2026 midterm elections. The market resolves based on the official seat counts determined by regular and special elections, including runoffs, according to party attribution rules.
Early election results show significant Democratic gains as voters express frustration with the Republican Party. Notably, Democrat James Talarico defeated Ken Paxton in Texas, and Democrat Troy Jackson defeated incumbent Susan Collins in Maine.
Key figures in the recent races include James Talarico, Ken Paxton, Troy Jackson, and Susan Collins, alongside commentary from political leaders on the midterm outcomes.
Sources: PBS: WATCH: Democrat James Talarico speaks after winning Texas Senate seat, Politico: Voters pummel GOP out of power, Maine Public: Susan Collins concedes to Troy Jackson in Maine Senate race, The Guardian: Democrat Troy Jackson defeats Susan Collins to win Maine US Senate seat in blow to Republicans, Click2Houston: Ken Paxton concedes Texas U.S. Senate race to James Talarico, CBS News: Troy Jackson wins Maine 2026 Senate election, flipping seat for Democrats, NPR: Troy Jackson wins Maine Senate race over Susan Collins, in major coup for Democrats, PBS: Democrat Troy Jackson wins election to U.S. Senate from Maine, AP News: Democrats win US Senate, ending Republican dominance by harnessing voters' frustration with Trump
Written by AI from the linked news sources and checked automatically, not by a person.
What could move it next
No upcoming events listed for this market yet.
Price jumps explained
-
4 Nov 2026
Democrats Flip Maine Senate Seat
Early election results and news reports indicated that Democratic candidate Troy Jackson defeated Republican Senator Susan Collins in Maine, flipping the seat for Democrats. This result contributed to shifts in the Senate seat counts as reported on election night.
Sources: NBC News: Troy Jackson defeats GOP Sen. Susan Collins in Maine, padding Democrats’ majority, CBS News: Troy Jackson wins Maine 2026 Senate election, flipping seat for Democrats, NPR: Troy Jackson wins Maine Senate race over Susan Collins, in major coup for Democrats, PBS: Democrat Troy Jackson wins election to U.S. Senate from Maine, BBC: Republican Susan Collins loses seat, ending almost 30 years in the Senate
After 24 h: too early. After 7 days: too early.
-
29 Oct 2026
Polls Show Stronger Democratic Position in Senate Races
New polling data released around this time highlighted potential Democratic gains and paths to a Senate majority. These reports indicated that Democrats were within striking distance and leading across multiple key races.
Sources: https://ssrs.com/: Democrats in striking distance: New CNN polls in four states highlight Democrats' path to Senate majority, CNN: The range of outcomes in the 2026 battle for the Senate is enormous, DSCC: “SEEING BLUE”: New CNN Polls Show Democrats Leading “Across the Board,” “Well-Positioned” to Win Senate Majority With Days to Go
After 24 h: reverted. After 7 days: too early.
-
28 Oct 2026
Democrats Win Congress Scenarios Analyzed Ahead of Midterms
As the 2026 midterms approach, reports examine potential outcomes if Democrats win control of Congress. This analysis of legislative scenarios coincides with a drop in the likelihood of the Republican Party holding exactly 45 Senate seats.
Sources: Firstpost: What happens if Democrats win Congress in the 2026 US midterms?
After 24 h: held. After 7 days: reverted.
-
23 Oct 2026
Jump detected
Not explained yet. The write-up is added automatically, usually within a few hours.
After 24 h: held. After 7 days: held.
Written by AI from the linked news sources and checked automatically, not by a person.
Other markets in “Republican Senate seats after the midterms (Lower Brackets)”
Questions about this market
What are the odds for “Will the Republican Party hold exactly 45 Senate seats after the 2026 midterm elections”?
On 4 Nov 2026, Polymarket traders priced Yes at 18%, which means they saw about a 18 in 100 chance. That was up 12 points over the previous 7 days. The live price is shown in the chart at the top of this page.
Why did the odds move recently?
The latest explained move was on 4 Nov 2026, from 11% to 83%: Democrats Flip Maine Senate Seat. Early election results and news reports indicated that Democratic candidate Troy Jackson defeated Republican Senator Susan Collins in Maine, flipping the seat for Democrats. Every big move is listed under “Price jumps explained” (this one is number 4).
Do big jumps in this market usually hold?
Of the 3 big jumps old enough to check, 2 held after 24 hours (kept at least 70% of the move). The rest partly or fully reverted.
How does this market resolve?
This market will resolve according to the Republican Party’s seat count in the United States Senate as a result of the 2026 United States midterm election scheduled for November 3, 2026. The full Polymarket rules are at the bottom of this page.
Can I bet on this market on predictionwave?
No. predictionwave only explains the odds. The market itself runs on Polymarket, and trading there is not allowed in every country.
How this market resolves (Polymarket rules)
This market will resolve according to the Republican Party’s seat count in the United States Senate as a result of the 2026 United States midterm election scheduled for November 3, 2026. The seat count includes all regular and special Senate elections that determine representation in the upcoming 120th Congress and are scheduled to take place in November 2026 as of October 31, 2026. Runoffs for qualifying elections will determine attribution of the relevant seat, even if they take place after November 2026. Vacant seats for which no election or special election to fill the seat is scheduled to take place in November 2026 as of October 31, 2026 will be treated as held by the party affiliation of the most recent member to hold that seat. For seats contested in the specified election, seats are attributed to the party under which the member was elected. If a member-elect changes party affiliation, or vacates their seat, between election day and the formal organization of Congress, the seat is attributed to the party under which the member was elected. For seats not contested in the specified election, seats are attributed to the party that holds the seat as of the date of the election. If a current sitting member of the U.S. Senate who is not up for election changes party affiliation or vacates their seat after the date of the election, the seat is attributed to the party under which the member was affiliated at the time of the election. Senate members elected as independents who formally caucus with, or, for newly elected members, who announce their intent to caucus with, the Republican party are included in the count. If the caucus decisions of members of the Senate elected as independents cannot be determined on the date of the election, this market may remain open until the earlier of (i) an announcement from the relevant members of their intents to caucus, or (ii) January 4th, 11:59 PM ET of the following calendar year. If no such announcement is made by January 4th, 11:59 PM ET of the following calendar year, the member will not count towards the seat count of any party. The resolution sources for this market will be official information from relevant state electoral authorities, the United States Congress, and a consensus of credible reporting.