Republicans will maintain their six-year control over the U.S. House of Representatives, major TV networks projected on Tuesday night, and were also on track to defend their Senate majority, against a handful of failed Democratic challengers.

With Republican presidential nominee Donald Trump and Democratic rival Hillary Clinton locked in a close battle for the White House, television networks said Republicans, as widely projected by analysts, would keep control of the House.

Winners had been declared so far in 28 Senate races, with Democrats making a net gain of only a single seat so far, and only a handful of additional opportunities for them remaining undecided.

Some key races were still too close to call.

Party dominance in Congress will be a crucial determinant of the policy-making outlook for the next president.

The House has been in Republican hands since 2011 and has been a bastion of resistance to Democratic President Barack Obama’s agenda.

Democrats picked up a Senate seat from Republicans when Rep Tammy Duckworth, as expected, defeated Sen Mark Kirk in Illinois, according to the major TV networks.

Duckworth is a double-amputee Iraq war veteran.

With her victory, Democrats needed to pick up four more seats from Republicans to win a majority in the 100-member Senate.

But the Democrats lost opportunities to do that in several races, including Indiana, where networks projected that former Sen Evan Bayh failed in his bid to return to the Senate, losing to Republican Representative Todd Young.

The two were vying to replace Republican Dan Coats, who is retiring.

Similarly in Wisconsin, Democrat Russ Feingold’s effort to reclaim his former Senate seat fell short, with incumbent Republican Sen Ron Johnson prevailing, the networks said.

In North Carolina, Republican Senator Richard Burr was declared the winner over Democratic challenger Deborah Ross in another race where Democrats did not snag a hoped-for seat.

Republican dominance in Congress could stymie any legislative agenda Clinton might pursue, if she were elected.

A Trump victory, with a Republican Congress in place, could spell a swift demise for Obama’s health care reforms.

Republicans had to defend far more Senate seats this year than Democrats.

Some analysts had raised the possibility of the 2016 election season ending with a 50-50 split in the Senate.

In such an outcome, the new U.S. vice president – either Democrat Tim Kaine or Republican Mike Pence – would be the tiebreaker in the Senate and determine control of that chamber.

To win Senate control, Democrats would have to score a net, five-seat gain.

Republicans hold 54 Senate seats to 44 Democratic seats and two independents who align with Democrats.

In Florida, incumbent Sen Marco Rubio, who ran unsuccessfully for the Republican presidential nomination earlier this year, was declared the winner and was re-elected.

TV networks said Republican Sen Rob Portman, who refused to campaign with Trump, was re-elected in Ohio.

In the House of Representatives, Republican Liz Cheney was elected to the same Wyoming seat once held by her father, former Republican Vice President Dick Cheney.

(Reuters/NAN)