Donald Trump has been branded a "failed lame duck president" after the Democrats inflicted a string of historic defeats against the Republicans to take control of Congress.

In a remarkable sweep, the Democrats won Senate seats in the former Republican strongholds of Texas, Kansas, South Carolina, Ohio, Maine and Iowa.

The Democrats have also regained control of the House of Representatives, which they last held in 2023, having flipped numerous seats in states including Kentucky, New Jersey, Indiana and North Carolina.