WASHINGTON — Democrats won control of both chambers of Congress, flipping four Senate seats and notching key House of Representatives wins as the electorate, fed up over high prices and the war in Iran, cast their ballots in a referendum on US president Donald Trump’s second term.

In a stunning pair of Democratic victories in two of the most conservative states, James Talarico defeated Ken Paxton in Texas and Annie Andrews won an upset victory over Darline Graham in South Carolina, imperilling Republican control of the US Senate.

In Ohio, Democrat Sherrod Brown defeated Republican senator Jon Husted, marking another defeat in a Republican-leaning state. The historic outcomes were an extraordinary rebuke of Trump, who had thrown his full weight behind the losing candidates.

Trump had endorsed the scandal-plagued Paxton, the Texas attorney-general, over incumbent senator John Cornyn in the state’s Republican primary. Cornyn and national Republicans had warned that Paxton would struggle to win a general election, costing the party tens of millions of dollars, and potentially Republicans’ unified grip on power in Washington.

In South Carolina, Trump backed Graham despite doubts within his party that she lacked the experience and knowledge to win her brother Lindsey Graham’s seat after he died unexpectedly.

Trump repeatedly visited Ohio to campaign for Husted.

More than 59 million people had already cast ballots before election day, according to an Associated Press analysis, surpassing early-voter turnout from 2022.

Trump, whose party has struggled when he is not running to turn out the low-propensity voters who have fuelled his victories, told voters to act as though he’s on the ballot, even as many Republican candidates kept their distance.

But as Democrats racked up victories. Trump rushed to duck blame for his party’s losses before polls on the west coast had even closed.

“I wasn’t on the ballot and if I was, we would have won in a landslide!” he wrote on his social-media site.

Democrats had already flipped North Carolina and hung on to competitive seats in New Hampshire and Georgia.

Beyond Washington, 36 states elected governors. Democrats Josh Shapiro in Pennsylvania, JB Pritzker in Illinois, Wes Moore in Maryland, Maura Healey in Massachusetts and Kathy Hochul in New York all won re-election.

In a stunning upset, Gina Hinojosa defeated Republican governor Greg Abbott. In Ohio, Republican Vivek Ramaswamy lost to Democrat Amy Acton after his campaign faced backlash for an advert featuring Acton’s estranged mother, who lost custody of Acton decades ago after her husband, Acton’s stepfather, was indicted for raping Acton as a child.

Democrat Keisha Lance Bottoms, of Georgia, will be the first Black female governor of any state. In neighbouring Florida, Byron Donalds became the first Black Republican to be elected governor in the nation.

The results will shape the final two years of Trump’s second term.

The Republican-controlled Congress acted as a rubber stamp for much of his agenda.

While Trump has proven adept at steamrollering efforts to rein him in, Democrats taking control of even one chamber would open the floodgates to investigations and possible impeachments.

Defence secretary Pete Hegseth and tech titan Elon Musk, a former top Trump adviser, are among possible targets.

House Democratic Leader Hakeem Jeffries, of New York, in line to make history as the nation’s first Black Speaker of the House if his party sweeps to power, has outlined a 100-day agenda focused on lowering the cost of living and aggressively overseeing the Trump Administration.

Democratic senator Jon Ossoff won re-election in Georgia, defeating representative Mike Collins and denying Republicans a seat they had once seen as a top pick-up opportunity. Representative Chris Pappas won a Senate race in New Hampshire, defeating former senator John Sununu to replace retiring Democrat Jeanne Shaheen.

In the House, Democrats were marching towards control after defeating six Republicans in key battleground races.

Republican representatives Tom Kean, of New Jersey, and three Republicans in Pennsylvania, Ryan Mackenzie, Scott Perry and Rob Bresnahan, lost re-election and Democrats won open seats in North Carolina and Kentucky.

The elections could drastically shift power in Washington. Democrats had been cautiously optimistic as they watched Republicans spend the campaign’s final stretch pumping tens of millions of dollars into states and districts that Trump won handily two years ago, and watched Trump campaign across some of the reddest states.

They had bet that discontent over Trump’s failure to stop inflation and perceptions that he is focused more on gilding the nation’s capital than easing their pain at the pump will turn the tide in their favour.

Republicans had held out hope their money advantage would help stem the tide.

Several Democratic senators easily won re-election, including senators Cory Booker in New Jersey, Ed Markey in Massachusetts and John Hickenlooper in Colorado.

Democrat Juliana Stratton was elected to replace Democrat Dick Durbin.

On the Republican side, senator Ashley Moody won a special election in Florida to finish the term of Marco Rubio, who became Trump’s secretary of state in 2025. Wyoming representative Harriet Hageman won a Senate seat in Wyoming, replacing retiring Cynthia Lummis.

In the House, Democrat Jamie Ager beat Republican Jennifer Capps Balkcom in North Carolina to give the party its first House flip.

Another Democratic flip came in New Jersey, where former Navy helicopter pilot Rebecca Bennett defeated representative Tom Kean, who missed four months of votes in Washington this year as he underwent treatment for depression, a diagnosis he did not disclose until his return.