Democrats need to gain four seats from Republicans to secure control of the 100-member US Senate in the November 3 midterm elections. Although voters will choose candidates across 35 states, only nine contests are currently considered competitive by independent political analysts.
North Carolina
North Carolina is one of the Democrats’ strongest opportunities to gain a Republican-held seat after Senator Thom Tillis announced his retirement.
Polling has shown former Democratic Governor Roy Cooper maintaining a lead over Republican Michael Whatley, a Trump ally who most recently served as chairman of the Republican National Committee.
Cooper has a strong electoral record in the state, having won two terms as governor and four elections as attorney general, including victories in years when Donald Trump also carried North Carolina.
Whatley has extensive political experience but has never previously held elected office. His close association with Trump could prove challenging, particularly as the president’s approval rating stands at 33 per cent, according to Reuters/Ipsos polling.
Michigan
Democrats are defending an open Senate seat in Michigan following Senator Gary Peters’ retirement.
Democratic nominee Abdul El-Sayed, a progressive former health official, narrowly won a divisive primary against centrist Representative Haley Stevens. His criticism of Israel and association with left-wing streamer Hasan Piker helped mobilise progressive voters but also generated resistance among some Black and Jewish voters.
El-Sayed faces Republican Mike Rogers, a former House member who lost a Senate contest in 2024.
The race remains closely fought and is rated a toss-up by nonpartisan analysts, who say El-Sayed’s progressive positioning could make it harder for him to win over independent voters.
Texas
Texas, traditionally a Republican stronghold, has unexpectedly become a battleground.
Democratic state Representative James Talarico is challenging Republican Ken Paxton, the state attorney general, in a closely watched contest.
Paxton defeated incumbent Senator John Cornyn in a contentious Republican primary with Trump’s backing, despite having faced allegations of marital infidelity that nearly led to his removal from office in 2023.
Since winning the nomination, Paxton has faced fundraising difficulties, prompting Republicans to spend heavily to protect what would normally be regarded as a safe seat.
Talarico is seeking support from independents and Republicans unhappy with the party. However, previous comments he made about gender identity could leave him vulnerable to Republican attacks.
Independent analysts currently rate the contest a toss-up.
Alaska
Republican Senator Dan Sullivan faces a competitive challenge from Democrat Mary Peltola, as well as an unusual complication involving another candidate with the same name.
Peltola, a centrist Democrat who previously served one term in the House, received 82,000 votes compared with Sullivan’s 69,000 in Alaska’s nonpartisan primary in August.
Sullivan will also face retired teacher Dan J. Sullivan, another Republican who secured enough support to advance to the November election despite efforts by Republicans to remove him from the ballot.
Peltola could benefit from Alaska’s ranked-choice voting system, which allows voters to rank candidates and takes second preferences into account.
Polling has been limited, but analysts consider the race a toss-up.
Iowa
Iowa could produce one of the most competitive Senate races of the election after years of Republican dominance.
Republican Representative Ashley Hinson is seeking to retain the seat following Senator Joni Ernst’s retirement. She faces Democratic state Representative Josh Turek, a former Paralympic basketball player who has highlighted his record of bipartisan work in the state legislature.
Trump’s tariffs and high fuel prices have become important issues in the farm state.
Polling indicates a close contest, with analysts expecting the race to be among the most competitive Senate battles this autumn.
Maine
Democrats were forced to find a new candidate in Maine after progressive candidate Graham Platner withdrew in July following accusations of sexual assault, which he denied.
The party quickly rallied behind Troy Jackson, a former lumberjack and state legislator who shares Platner’s progressive politics.
Jackson, 58, is challenging Republican Senator Susan Collins, a moderate who has occasionally broken with her party.
Collins, first elected in 1996, has repeatedly won re-election even as Maine has consistently supported Democratic presidential candidates.
Recent polling has shown Jackson with a narrow lead of between three and four percentage points.
Georgia
Democratic Senator Jon Ossoff is seeking another term against Republican Representative Mike Collins, a conservative candidate backed by Trump.
Georgia has become one of the country’s key battleground states. Trump narrowly won the state in the 2024 presidential election, while Ossoff secured his Senate seat in a closely fought 2021 runoff.
At 39, Ossoff is also viewed by some Democrats as a potential presidential contender in 2028.
Collins has built a provocative social media presence that has occasionally caused controversy. In 2024, he was criticised after suggesting that President Joe Biden had directed an assassination attempt against Trump.
More recently, his campaign has faced scrutiny over racist posts made by a former aide, which the campaign has disavowed.
Most polls have given Ossoff the advantage, and nonpartisan analysts currently rate him as the stronger candidate.
Ohio
Former Democratic Senator Sherrod Brown is attempting to return to the Senate after losing his seat to Republican Bernie Moreno in 2024.
Brown, a long-time advocate of economic populism, is challenging Republican Senator Jon Husted, who was appointed to the seat in 2025 after JD Vance resigned to become Trump’s vice president.
Husted previously served as Ohio’s lieutenant governor and secretary of state.
Ohio has moved increasingly towards the Republican Party over the past decade, and Trump won the state by 11 percentage points in 2024.
However, recent polling has put Brown three to four points ahead, leading analysts to classify the race as a toss-up.
The winner will serve the remainder of Vance’s Senate term, which runs until January 2029.
New Hampshire
New Hampshire’s September 8 primary will determine the candidates competing for the Senate seat being vacated by Democratic Senator Jeanne Shaheen.
Republicans are expected to nominate former Governor John Sununu, who previously served in the Senate from 2003 to 2009. Democratic Representative Chris Pappas is leading his party’s field.
Despite the competitive nature of several other Senate contests, nonpartisan analysts currently consider Democrats favoured to retain this seat.