The US Democrats have taken control of the House of Representatives in the mid-term elections. Taking control of the lower chamber of Congress for the first time in eight years will enable Democrats to thwart the president's agenda. But Mr Trump's Republicans are set to strengthen their grip on the Senate.
Tuesday's vote was seen as a referendum on a polarizing president, even though he is not up for re-election till 2020. Female candidates stole the spotlight in an election cycle that had been billed as the Year of the Woman.
Democrats converted the energy of the liberal anti-Trump resistance into solid electoral gains in the first nationwide vote since the president swept to power two years ago.
The BBC's US partner network CBS projects the Democrats will win the 23 seats they need to take over the lower chamber of Congress. Americans voted for all 435 seats in the House. The Democrats could now launch investigations into Mr. Trump's administration and business affairs, from tax returns to potential conflicts of interest.
They could also more effectively block his legislative plans, dooming his signature promise to build a wall along the border with Mexico.
A record number of women ran for office in this election. New York Democrat Alexandria Ocasio-Cortez is projected to become the youngest ever congresswoman, at 29 years old.
Democrats Ilhan OImar and Rashida Tlaib made history in Minnesota and Michigan respectively as the first Muslim women elected to Congress. Democrats Sharice Davids of Kansas and Debra Haaland from New Mexico will become the first Native American women elected to Congress.
Ms Davids, a former cage-fighter, is also the first openly gay representative from Kansas. Ayanna Pressley was elected as Massachusetts' first black congresswoman.
Democratic House leader Nancy Pelosi told cheering Democrats at a Washington victory party: Thanks to you, tomorrow will be a new day in America.
Republicans are on course to expand their slim 51-49 majority in the upper chamber of Congress. Three Democratic incumbents - Joe Donnelly in Indiana, Claire McCaskill in Missouri and Heidi Heitkamp in North Dakota - suffered defeat to Republican challengers.
A fourth Democrat - Bill Nelson in Florida - looks likely to be unseated, too. Republican Texas Senator Ted Cruz fended off a strong challenge by Democratic rising star Beto O'Rourke.
And Republican Marsha Blackburn became Tennessee's first woman senator, despite an endorsement for her male Democratic challenger from pop star Taylor Swift.
Democratic Senators Joe Manchin and Bob Menendez held on after tough campaigns in West Virginia and New Jersey respectively, but it was cold comfort.
Mitt Romney, the 2012 Republican presidential nominee, has won his Senate race Utah, as expected.
Democrats were always facing an uphill battle in the Senate this year because they were defending 26 seats, while just nine Republican seats were up for grabs.
The party in power historically tends to lose a number of congressional seats during the first mid-term election of a new president, particularly if his national popularity rating is low.