US Senate Races 2026: The Seats That Could Change Party

Any of the 35 US Senate seats on the ballot on Tuesday 3 November 2026 can change party; this guide covers 12 races with a versus prediction on the winner, four for seats Democrats hold and eight for seats Republicans hold. At 06:53 UK time on 27 October 2026, the versus prediction on the Republican seat count showed 5.6p for exactly 53 seats, the number the party holds now, which is the market's estimate of a 5.6% chance.

The Library of Congress's Congress.gov member data showed 53 Republicans, 45 Democrats and 2 independents in the Senate on 27 October 2026, and the Federal Election Commission's 2026 primary calendar marks Senate elections in 35 states. Eleven of the 12 are also in the versus predictions on the tightest contest and on margins within 5 points. Control of the chamber is covered in our midterms guide.

This guide is for readers in Great Britain, and every reading below was taken at 06:53 UK time on 27 October 2026. A price from 0p to 100p is the market's estimate of a chance, and versus does not say who will win (how to read market probabilities). Seat holders come from Congress.gov, open seats from FEC data, and candidate names from the state's own list where one is cited, otherwise as the prediction lists them.

Seats Democrats are defending

• Michigan: open seat held by Gary Peters (Democratic). In the Michigan Department of State's 4 August primary results, Abdul El-Sayed won for the Democrats and Mike Rogers for the Republicans. The Michigan prediction showed 68.5p for El-Sayed and 31.5p for Rogers.
• Georgia: held by Jon Ossoff (Democratic). The Georgia prediction lists Jon Ossoff (D) and Mike Collins (R) and showed 95.7p and 4p.
• New Hampshire: open seat held by Jeanne Shaheen (Democratic). The New Hampshire prediction lists Chris Pappas and John E. Sununu, a Democrat and a Republican in FEC data, and showed 91.5p and 8.5p.
• Minnesota: open seat held by Tina Smith (Democratic). The Minnesota prediction lists Peggy Flanagan (D) and Michele Tafoya (R) and showed 85.5p and 14.5p.

Seats Republicans are defending

• Maine: held by Susan Collins (Republican). The Secretary of State's candidate list names Susan M. Collins (Republican) and Troy D. Jackson (Democratic). The Maine prediction showed 38.5p for Collins and 60.5p for Jackson.
• North Carolina: open seat held by Thom Tillis (Republican). The State Board of Elections lists Roy Cooper (Democratic), Michael Whatley (Republican), Shannon W. Bray (Libertarian) and Michael Dublin (Green). The North Carolina prediction showed 97.1p for Cooper and 2.7p for Whatley.
• Ohio: held by Jon Husted (Republican). The Ohio prediction lists Sherrod Brown (D) and Jon Husted (R) and showed 68.5p and 31.5p.
• Iowa: open seat held by Joni Ernst (Republican). The Iowa prediction lists Josh Turek (D) and Ashley Hinson (R) and showed 42p and 58.5p.
• Texas: held by John Cornyn (Republican). The Texas prediction lists James Talarico (D) and Ken Paxton (R) and showed 67p and 33.5p.
• Alaska: held by Dan Sullivan (Republican). The Alaska Statutes put the four leading primary candidates on the general ballot and count the general election by ranked choice. The Alaska prediction, set up on 6 July before the state's 18 August primary, lists five names, one more than the four the statute puts on the ballot: Dan Sullivan, Mary Peltola, Ann Diener, Dustin Darden and Richard Grayson. It showed 25.5p for Sullivan and 73.5p for Peltola; ten others, such as Peltola by under 3 points, cover only the first-round lead.
• Nebraska: held by Pete Ricketts (Republican). The Secretary of State's final candidate list has Pete Ricketts (Republican), Dan Osborn (By Petition), Mike Marvin (Legal Marijuana NOW), Robin Richards (Nebraska Working People) and Chuck Conboy (America First), and no Democrat. The Nebraska prediction showed 72p for Republican and 28.5p for Independent.
• Louisiana: held by Bill Cassidy (Republican). From 2026 the two major parties choose Senate nominees in closed party primaries (16 May, second round 27 June), and the most votes wins the general election, no majority needed, the Secretary of State says. Its candidate inquiry lists "Jamie" Davis (Democrat) and Julia Letlow (Republican). The Louisiana prediction showed 89.5p for Republican and 10.5p for Democrat.

Predictions across several races

The within 5 points prediction asks, state by state, whether the top two finish 5 percentage points apart or less; it showed 72p for Texas and 68.5p for Maine. The core four prediction needs Democratic wins in all of Maine, Georgia, Michigan and North Carolina and showed 54p for Yes.

How our predictions settle

The single-race predictions other than Nebraska's and Louisiana's settle once the Associated Press, NBC and Fox News have all named the same winner, or else on the official certified result. Runoffs count, a party's answer covers only its nominee, and independents never count under a party answer. Alaska's adds a cut-off: with no confirmed result by 31 July 2027 it settles as Other, outside its five names. New Hampshire's uses the same outlets, moves a party's answer to any replacement nominee and settles No for both names if neither wins. The Nebraska and Louisiana rules follow the election's winner, runoffs included, count only official nominees for a party and name no outlet (what market resolution means).

The seat count adds up Republican seats from all November Senate elections scheduled by 31 October, waits for any runoff that could change the total, and settles when the same three outlets have called every race, or on certification; a winner with neither party's ballot label counts with whichever they last said they would caucus with. The within 5 points prediction uses each state's election authority and, for multi-round counts, the deciding round. The core four settles the same way as the single races.

Trading on the core four and on each of the 12 predictions on the winner except New Hampshire's ends at 00:00 GMT on Tuesday 3 November, 7pm on Monday in New York; the ten Alaska first-round predictions close at 12:00 GMT the same day. The seat count closes at 17:00 GMT on 3 November, the within 5 points prediction at 23:59 GMT, and New Hampshire's at 04:59 GMT on 4 November. A close stops trading, not the question (when markets close).

Election night and after, in UK time

US clocks go back on Sunday 1 November (NIST, the US standards agency), so on polling day New York is five hours behind the UK.

• Tuesday 3 November: polls close at 7:30pm in North Carolina, 00:30 GMT on 4 November (State Board of Elections); at 8pm local time in Michigan, 01:00 GMT on 4 November where Eastern time applies (Department of State); and at 8pm Central time in Louisiana and Nebraska (7pm in Nebraska's Mountain time area), 02:00 GMT on 4 November. Most single-race predictions then wait for calls by AP, NBC and Fox News.
• Tuesday 1 December: the FEC's reporting calendar date for any Georgia general election runoff, which the Georgia prediction, the core four and the seat count would wait for.
• Sunday 3 January 2027: the 20th Amendment ends the outgoing senators' terms at noon, 17:00 GMT, and their successors' terms begin.

Before you trade

You can lose the whole amount you put into a position: an answer that does not come true settles at 0p. A 2% transaction fee is added on top of the stake and shown before you confirm, you can sell at the current price while a prediction is open, and your loss can never exceed what you put in. versus is licensed by the UK Gambling Commission under account 101143 (public register), and Safer Play has deposit limits, loss limits, reality checks, time out and self exclusion, alongside GAMSTOP.

Frequently asked questions

Could the Georgia Senate race go to a runoff?

The FEC's calendar lists a Georgia general election runoff on Tuesday 1 December 2026, and the versus Georgia prediction would wait for it.

How does Alaska count its Senate votes?

By ranked choice. Under section 15.15.350 of the Alaska Statutes, a candidate ranked first on more than half the active ballots wins; otherwise the last-placed candidate drops out and those ballots move to their next choice.

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