What it would take for Democrats to win the US Senate

An unpopular war in the Middle East and voters’ discontent with the cost of living have put Democrats within striking distance of repeating a historic victory notched exactly two decades ago, when the party pulled off a stunning Senate upset to win control of the US Congress. 

A Democratic-controlled Senate could block US President Donald Trump’s nominees, including to the Supreme Court, investigate the President and his allies, hold leverage over the federal budget and set the rules for a potential third Trump impeachment trial.

Democrats have long been favoured to win the House, where they need to pick up just a handful of seats across the country. The path to Senate victory is narrower and more arduous, requiring the party to pick up at least four seats, including at least three in states Mr Trump won. 

It is a stretch, especially with Republicans holding a fund-raising advantage, including a plan this week by the Republican Party-aligned Senate Leadership Fund to allocate US$342 million (S$436 million) to the key battlegrounds. But Democrats have history and momentum on their side. In 2006, another Republican president with fading popularity in the middle of his second term – Mr George W. Bush – lost both the House and, more surprisingly, the Senate amid waning support for the war in Iraq.

Democrats’ chances likely hinge on four states where they are seen as most competitive, and several more that are potentially in play. They will then have to stave off well-funded Republican efforts to flip several Democratic-held seats, including two in states won by Mr Trump, with the Republican Party touting Mr Trump’s tax cuts and other issues that helped elect the President, like border security.

Top Democratic Targets

Alaska 

Former Democratic representative Mary Peltola’s decision to challenge Republican incumbent Dan Sullivan gives her party a plausible path to victory in what has usually been a reliably Republican state. Ms Peltola massively outperformed Ms Kamala Harris in 2024, though she still narrowly lost her House seat that year.

An Alaskan Native, Ms Peltola ran her previous campaigns on “fish, family and freedom” as a way to frame positions on issues like healthcare, taxes and abortion that are in line with the Democratic mainstream – as well as support for oil drilling and gun ownership that can be at odds with the national party.

Mr Sullivan faces headwinds from Mr Trump’s tariffs, especially on neighbouring Canada, as well as the expiration of some Affordable Care Act (ACA) tax credits for health coverage, which has a disproportionate effect on Alaskans, who already face some of the highest consumer prices in the nation. Mr Sullivan can point to his strong resistance to then President Joe Biden’s restrictions on the state’s oil and gas industry.

North Carolina

Democrats’ best pick-up opportunity could be in North Carolina, a classic swing state where popular former Democratic governor Roy Cooper has been leading Republican Michael Whatley in early polls to succeed retiring Republican Senator Thom Tillis in a race that some experts think will set a new record for Senate campaign spending. 

Mr Tillis, a vocal Republican maverick, has been sounding the alarm over the political danger his party faces over Mr Trump’s health care cuts, which he said will hit his state’s finances harder than any other and risks prompting a Democratic wave election. 

Mr Whatley chaired the Republican National Committee during Mr Trump’s 2024 presidential campaign and remains a close ally of the White House.

Maine

Republican Susan Collins, the chairperson of the powerful Appropriations Committee, is seeking a sixth term, but has the tough task of trying to hold on to the only Republican-held Senate seat up for election in a state Mr Trump lost in 2024. Mr Trump lost by 7 percentage points in that race.

As in Alaska, tariffs opposed by Ms Collins have hit Maine’s economy, particularly a tourism industry that has long benefited from Canadian visitors crossing the border. And Mainers on ACA health plans face soaring premiums after Ms Collins’ fellow Republicans refused to extend expiring subsidies. Ms Collins has long touted her ability to bring appropriations back to the state, as well as work with Democrats, and she won handily in 2020 despite massive spending to try and defeat her and many polls suggesting that she would lose. But that was also before the conservative Supreme Court majority she helped install overturned Roe versus Wade.

Democrats are divided in a contentious primary between Governor Janet Mills, 78, and newcomer Graham Platner, a 41-year-old oyster farmer and veteran who is running an outsider campaign that has attracted crowds, millions in funding and a big lead in recent polls.

Ohio

Former Democratic senator Sherrod Brown is mounting a comeback bid after his 2024 defeat to Trump-allied car dealer Bernie Moreno. This round, Mr Brown faces off against Republican Senator Jon Husted, the former lieutenant-governor who filled the seat Mr J.D. Vance vacated when Mr Trump tapped him to become vice-president. Mr Brown needs to perform better than he did two years ago in traditionally Democratic industrial areas such as the Mahoning Valley, areas that Mr Trump and Mr Moreno swung to the Republican Party.

Like other Democrats, Mr Brown, a progressive populist with historically strong ties to unions, has been running on an affordability agenda and against health care cuts and tax cuts for the wealthy. Mr Husted, a reliable vote for Mr Trump, has sought to broaden his appeal by publicly seeking compromises on healthcare subsidies and voter ID legislation, though he has not succeeded in brokering deals on those issues. The Republican Senate Leadership Fund announced plans to spend a massive US$79 million here, more than it has allocated to any other state, and Republicans can hope crypto interests, which spent US$40 million to help defeat Mr Brown two years ago, will pile in again.

Longer shots

Texas

The Texas Senate race hinges in part on the outcome of the Republicans’ messy primary, which is set for a run-off in late May. Senate Republican leaders have been strongly backing incumbent John Cornyn, who warns that the party could lose the seat and hurt down-ballot House races if his challenger, Attorney-General Ken Paxton, wins. Mr Paxton has been plagued by accusations of infidelity, allegations of financial mismanagement and even faced a state impeachment trial on charges approved by the Republican-controlled state House. But he has savaged Mr Cornyn as insufficiently conservative. Mr Trump has dangled an endorsement in the intra-party fight but so far has not weighed in.

Democrats picked State Representative James Talarico, a Presbyterian minister-in-training who has campaigned as a bridge-builder to independent and disaffected Republican voters. In the primary, he performed well in heavily Latino counties in South Texas and El Paso, a sign that he may be able to win back some of the Hispanic voters who shifted to Mr Trump in 2024. 

Iowa

Democrats have their best chance to take an Iowa Senate seat since progressive Tom Harkin won in 1984. Republican Joni Ernst, who succeeded Mr Harkin 12 years ago, isn’t running again. National Republicans have got behind Representative Ashley Hinson as their candidate, while Democrats Josh Turek and Zach Wahls are competing for their party’s nomination.

Iowa’s farm community and economy have been hit by foreign trading partners’ retaliation against Mr Trump’s tariffs. Surging fuel and fertiliser costs in the wake of the war on Iran are now adding to financial burdens. Most of the state’s electricity comes from wind power, which Mr Trump has repeatedly targeted. 

Nebraska

Mr Dan Osborn, an independent veteran and union leader who ran an unexpectedly strong campaign in 2024 is back, this time taking on incumbent Republican Pete Ricketts, the former governor and member of the family that owns the Chicago Cubs. Early polls show a close race, though betting markets and most political prognosticators expect Mr Ricketts to prevail.

Montana

Senator Steve Daines’ shock withdrawal from the race and endorsement of US Attorney Kurt Alme to replace him minutes before the filing deadline has provoked controversy in a state that had been seen as a safe Republican hold. A potentially strong independent candidate, Mr Seth Bodnar, has launched his own outsider campaign. Mr Bodnar is a former president of the University of Montana and was a Green Beret after graduating from West Point.

Republican Targets

Georgia 

Senator Jon Ossoff, whose narrow run-off win in 2021 secured a 51-50 Democratic majority at the start of the Biden presidency, faces re-election in a state that has long been run by the Republicans and was won by Mr Trump in 2024. Mr Ossoff has been among the best Democratic fundraisers, while several Republicans are competing in a contentious Republican primary. Among the issues are healthcare, taxes and immigration policy.

Michigan

With Democrat Gary Peters retiring, the party has several candidates vying for the nomination in a state that also narrowly voted for Mr Trump. Republicans have endorsed Mr Mike Rogers, the former House Intelligence chairman who lost narrowly two years ago to Democrat Elissa Slotkin. 

New Hampshire

Democrat Jeanne Shaheen’s retirement sets up another open seat in a purple state, albeit one Mr Trump lost three times. Democratic Representative Chris Pappas has the backing of national Democrats. Former Republican senator John Sununu, who was defeated by Ms Shaheen in 2008, is seeking a comeback with the backing of Republican leaders. He faces off against Mr Scott Brown, a former Massachusetts senator who lost that seat in 2012 and then was defeated by Ms Shaheen in 2014, for the Republican renomination. BLOOMBERG