Republicans face a difficult defence of their US Senate majority as the midterm elections approach, with Democrats needing to gain at least four seats to take control of the 100-member chamber.
October polling has shown Democratic candidates leading nationally and in several of the states likely to decide the outcome. Yet Republicans have enjoyed a major fundraising advantage, both across the country and in key battlegrounds.
President Donald Trump has also questioned whether conservative voters will turn out in force when he himself is not on the ballot. “If I don’t run, will those people go out and vote, and that’s the one thing I can’t tell,” he said recently, while urging Republicans to behave as though he were standing.
North Carolina is expected to be one of the Democrats’ likeliest early gains, but the broader contest will be shaped by a group of races stretching from Maine to Alaska. Candidates have faced allegations, personal controversies and bitter primary battles as both parties fight for control of Congress.
US Senate races that could decide control
Maine: Susan Collins, Republican, v Troy Jackson, Democrat
Republican Senator Susan Collins is fighting to retain her seat in Maine, which has one of the oldest electorates in the country. The Democratic nomination went to former state Senate president Troy Jackson after Graham Platner withdrew amid allegations of sexual misconduct and abuse, which he denies.
Jackson has faced controversy of his own after it emerged that he fathered children with his second cousin. The race has been classified as a toss-up, having previously been viewed as leaning Republican. A CNN/SSRS poll in the final week of October put Jackson on 49 per cent and Collins on 45 per cent, although Collins has previously outperformed poor polling on election day.
Georgia: Jon Ossoff, Democrat, v Mike Collins, Republican
Jon Ossoff, 39, is regarded as one of the Democratic Party’s rising figures and is strongly favoured in his contest against Republican congressman Mike Collins.
Collins has been hit by claims involving his campaign and family. His son-in-law was reported to have shared white supremacist rhetoric, while senior advisers were referred to the House Ethics Committee over an alleged misuse of funds. The race has moved from likely Democrat to more firmly Democratic in recent assessments.
Ossoff has led in recent polling, including an Echelon Insights survey which gave him 55 per cent support compared with 40 per cent for Collins.
New Hampshire: Chris Pappas, Democrat, v John Sununu, Republican
Democratic Senator Jeanne Shaheen’s decision not to seek a fourth term has given Republicans an opportunity in New Hampshire, although Democrats remain favoured to hold the seat.
Republican candidate John Sununu has a well-known name in state politics and has previously served in both the US House and Senate. His campaign is also supported by the popularity of Republican governor Kelly Ayotte.
A UMass Lowell poll conducted during the first half of October gave Democratic congressman Chris Pappas a seven-point lead, with 48 per cent backing him and 41 per cent supporting Sununu. The contest was briefly rated a toss-up before shifting towards the Democrats.
Ohio: Jon Husted, Republican, v Sherrod Brown, Democrat
Republican Jon Husted is seeking election after being appointed to Ohio’s Senate seat when JD Vance vacated it to become vice-president. He faces a comeback attempt by Sherrod Brown, the 73-year-old Democrat who previously held the seat.
Brown has faced criticism after video emerged in which he discussed a lack of diversity among congressional staff and referred to “black and brown” night cleaners.
The contest is rated a toss-up. An Echelon Insights poll in the third week of October placed both candidates on 47 per cent, while prediction-market users were reported to be backing Brown by 66 per cent to 34 per cent. Whoever wins will have to stand again in 2028.
Iowa: Ashley Hinson, Republican, v Josh Turek, Democrat
Republican congresswoman Ashley Hinson is contesting a statewide election for the first time, having represented eastern Iowa since 2021. Her Democratic opponent, state lawmaker Josh Turek, emerged from a bruising primary backed by senior figures in his party.
Former president Barack Obama recorded a basketball-themed advert with Turek, a former Paralympic basketball player. The race is taking place in a state that leans Republican, but Democrat Rob Sand’s performance in the gubernatorial contest could affect turnout.
The seat shifted from leaning Republican to a toss-up. An Echelon Insights poll found Turek narrowly ahead, on 45 per cent to Hinson’s 43 per cent.
Michigan: Mike Rogers, Republican, v Abdul El-Sayed, Democrat
Michigan is among the most closely fought Senate contests. Abdul El-Sayed secured the Democratic nomination by a single point over congresswoman Haley Stevens, raising questions about whether his support among the party’s progressive base will carry into the general election.
El-Sayed performed strongly among Arab-American and younger voters, while Stevens attracted greater support from older Democrats and African-American voters. El-Sayed has since sought to broaden his appeal, appearing at a rally with former vice-president Kamala Harris and planning another event with Barack Obama.
Republican Mike Rogers, a former House member, had been waiting for the Democratic primary to produce his opponent. The contest remains rated a toss-up, although a CNN/SSRS poll gave El-Sayed a seven-point lead, with 49 per cent compared with Rogers’s 42 per cent.
Texas: Ken Paxton, Republican, v James Talarico, Democrat
Republicans are also defending what had been regarded as a relatively safe seat in Texas. Attorney General Ken Paxton won a divisive Republican primary with Trump’s endorsement, defeating incumbent Senator John Cornyn, while James Talarico overcame Democratic firebrand Jasmine Crockett.
Paxton’s campaign has been overshadowed by allegations of adultery during a bitter divorce and by his previous impeachment, though he was acquitted by fellow Republicans in the Texas Senate. He nevertheless emerged from a primary dominated by Christian evangelical voters.
Republican governor Greg Abbott is seeking a historic fourth consecutive four-year term, a campaign expected to boost turnout for Paxton. The Senate race has moved from leaning Republican to a toss-up, however, and a CNN/SSRS poll put Talarico six points ahead, on 49 per cent to Paxton’s 43 per cent.
Nebraska: Pete Ricketts, Republican, v Dan Osborn, independent
Independent Dan Osborn is making a second statewide run in Nebraska after losing to a Republican in 2024. This time he is challenging Pete Ricketts, the incumbent senator and former governor.
Osborn’s campaign has faced scrutiny over claims that he paid himself and family members nearly half a million dollars from campaign funds. His daughter’s participation in adult-oriented online platforms has also drawn attention.
Ricketts is still considered likely to retain the seat. An Echelon Insights poll showed him just one point ahead, with 47 per cent to Osborn’s 46 per cent, while the race remains rated likely Republican.
Alaska: Dan Sullivan, Republican, v Mary Peltola, Democrat
Republican Senator Dan Sullivan, who has held Alaska’s junior Senate seat since 2015, faces former congresswoman Mary Peltola, whose moderate record in the House has made her a serious challenger.
Peltola finished ahead of Sullivan in August’s open primary, taking 48.2 per cent of the vote to his 42.9 per cent. A second candidate named Dan Sullivan, a retired teacher, is also on the ballot, while ranked-choice voting adds another layer of uncertainty.
A report alleged that Peltola’s allies had helped recruit the second Dan Sullivan in an effort to confuse voters. The contest is rated a toss-up, and an InsiderAdvantage poll of 1,200 likely voters put Peltola ahead on 50 per cent to 48 per cent.
Kansas: Roger Marshall, Republican, v Adam Hamilton, Democrat
Republican Senator Roger Marshall is defending a seat Democrats have not won for almost a century. His opponent is Adam Hamilton, a pastor at one of the largest churches in the Kansas City metropolitan area.
Marshall has faced criticism over revelations that, before entering Congress, he sued more than 700 former patients over unpaid medical bills. He has dismissed the report as a Democratic hit job, saying only “a very small, small, small fraction of the unpaid bills even went to collections”.
Trump has defended Marshall, describing him as “great, a wonderful person” who had been given a “bum rap” because he was legally required to seek money owed by patients. The race shifted from leaning Republican to a toss-up, and an October CNN/SSRS poll gave Hamilton a four-point advantage, with 49 per cent support compared with 45 per cent for Marshall.
