Democrats have won control of both chambers of Congress, delivering a decisive rebuke of Republican governance in Washington and ushering in a new era of congressional resistance to President Donald Trump. Democrats are projected to win 54 seats in the Senate against 44 for Republicans, while they would grab 236 seats in the House of Representatives as Trump's party would get 146 seats.
Republicans were defending a majority in the 435-member House. Democrats held 212 House seats and needed 218 to win control.
Members of the House of Representatives serve two-year terms and face re-election every even year. Democrats clinched a majority of governorships for the first time in 16 years, further punctuating the party's success across the map.
Democrats have so far attained 28 governorships while Republicans got 20. Voters punished Trump's allies almost everywhere.
Democrats won in swing states like Georgia, Michigan, New Hampshire, and North Carolina, and in Republican strongholds of Iowa, Kansas, Texas, and even South Carolina. Trump's controversial mid-decade redistricting plan appeared to backfire.
Republicans have not won any of the House or Senate races that were widely seen as competitive before voting began on Tuesday. Democrats have won more than two dozen competitive House races, plus a handful that were thought to have favoured Republicans.
Tuesday's midterm elections laid bare voters' deep frustrations over high prices, the Iran war, and concerns over government corruption. Democrats routed their rivals across the map, flipping states that have voted Republican for decades and that Trump won by double digits just two years ago.
That includes James Talarico's stunning Senate victory in Texas, where no Democrat had won statewide office in more than 30 years, and Annie Andrews' upset victory over Senator Darline Graham in South Carolina. Trump had thrown his full weight behind both losing candidates.
In Michigan, progressive Muslim Abdul El-Sayed - one of a crop of left-wing candidates who prevailed in Democratic primaries - topped Republican Mike Rogers. Even Republican Senator Susan Collins of Maine, a battle-tested survivor of difficult elections, lost to Democrat Troy Jackson.
Abdul El-Sayed has become the first Muslim person elected to the US Senate. The results marked a fundamental unraveling of the coalition that returned Trump to the White House two years ago, with young people and Latinos moving away from Republicans, according to The Associated Press (AP) Voter Poll.
Only about one-third of Hispanic voters said they backed the Republican in their local US House races. It was a major blow to Trump, who spent nearly every day of the last month holding rallies to energise his supporters but was unable to stop a wipeout.
While Trump has proven adept at steamrolling efforts to rein him in, Democratic control will profoundly reshape Trump's final two years in office and hamstring his legislative agenda. Party leaders have signaled they'll use their new power to ensure Trump's final two years in office are dominated by a series of investigations of top members of his administration.
Impeachment of Trump and his cabinet officials is not off the table. Defence Secretary Pete Hegseth and tech titan Elon Musk, a former top Trump adviser, are among possible targets for investigations.
The US president, unlike a prime minister in a parliamentary system, does not resign upon losing a majority.