WASHINGTON Republicans on Saturday appeared close to clinching control of the US House of Representatives, a critical element for President-elect Donald Trump to advance his agenda when he returns to the White House in January.

With votes still being counted from the Nov 5 general election, Republicans had won 212 seats in the 435-member House, according to Edison Research, which projected on Friday night that Republican Jeff Hurd had enough votes to keep Republican control of Colorado's 3rd congressional district.

Republicans need to win six more seats to keep control of the House and they already have enough victories to wrest control of the US Senate from Democrats, though Edison Research projected late on Friday that Democratic US Senator Jacky Rosen won re-election in Nevada.

With Trump's victory in the presidential election and Republican control of the Senate already decided, keeping hold of the House would give Republicans sweeping powers to potentially ram through a broad agenda of tax and spending cuts, energy deregulation and border security controls.

Results of 19 House races remain unclear, mostly in competitive districts in Western states, where the pace of vote counting is typically slower than in the rest of the country.

Ten of the seats are currently held by Republicans and nine by Democrats. Fourteen seats were widely seen as competitive ahead of the election.

Republican senators will decide next week as to who will serve as the party's leader in the Senate in 2025, with John Thune, John Cornyn and Rick Scott vying for the job. On Saturday, Senators Bill Hagerty and Rand Paul endorsed Scott over the more senior Thune and Cornyn, who have been viewed as favourites.

  - Reuters