US President Joe Biden has called the US midterm elections “a good day for America and democracy” after the Democrats seemingly defied bad polls to hold off a Republican surge.

Biden also took a subtle shot at former US president Donald Trump by declaring that a giant red wave “didn’t happen”.

The results are still trickling in, but the Republicans are inching towards a slim majority in the US House of Representatives on Wednesday (local time). However, the Senate may have eluded their grasp.

“While the press and pundits are predicting a giant red wave, it didn’t happen,” Biden said in a press conference on Wednesday (local time). “I know you were somewhat miffed by my obsessing optimism, but I felt good during the whole process.”

Speaking on whether Republicans would win the House back, Biden said, “It’s going to be close”.

If Republicans do claim majority, Biden said he would work with them but would not support “any Republican proposal that’s going to make inflation worse” or “[make us] walk away from historic commitments we just made to take on the climate crisis”.

Biden said it was his “intention” to run for president again in 2024.

When asked for his thoughts on the fact “two-thirds of Americans in exit polls think you shouldn’t run for re-election”, he had two words: “Watch me.”

US President Joe Biden also took a subtle shot at former president Donald Trump by declaring that a giant red wave 'didn’t happen'. Photo / AP

Trump didn’t get the “red wave” he wanted

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Biden’s Democrats outperformed expectations, and it was an underwhelming night for Donald Trump, who was counting on a big Republican showing to boost another White House run.

“While in certain ways yesterday’s election was somewhat disappointing, from my personal standpoint it was a very big victory – 219 wins and 16 losses,” Trump said, in a reference to candidates he personally endorsed.

“Who has ever done better than that?” the 76-year-old former president said on his Truth Social platform.

In addition to seeing several of his high-profile candidates lose, Trump also saw his main rival for the Republican presidential nomination in 2024, Ron DeSantis, notch up a thumping victory to remain governor of Florida.

Republicans appear to be on track to reclaim the 435-member House for the first time since 2018, but by a mere handful of seats.

Top Republican Kevin McCarthy put on a brave face after the party fell well short of picking up the 60 House seats he had once predicted.

“It is clear that we are going to take the House back,” said McCarthy, who hopes to be the lower chamber’s next Speaker.

With three key races yet to be called after Tuesday’s vote, the Senate remained in play, but it was leaning Democratic, and control may hinge on a run-off election in the southern state of Georgia in December.

While the night saw wins by more than 100 Republicans embracing Trump’s “big lie” that Biden stole the 2020 election, several hand-picked acolytes of the former president came up short.

“Many of the candidates he endorsed underperformed and cost their party a chance at picking up seats that should have been winnable,” said Jon Rogowski, a political science professor at the University of Chicago.

“Not only did voters reject many of Trump’s candidates, but they also rejected his policies,” Rogowski said, citing abortion as an example.

Former US president Donald Trump. Photo / AP

In ballot initiatives in five states, voters supported abortion rights in a rejection of the conservative-dominated Supreme Court’s ruling in June that overturned a constitutional right to the procedure.

‘Definitely not a Republican wave’

Aiming to deliver a rebuke to Biden against a backdrop of sky-high inflation and bitter culture wars, Republicans needed just one extra seat to wrest control of the evenly divided Senate.

But by Wednesday, the only seat to change hands went to the Democrats, with John Fetterman, a champion of progressive economic policies, triumphing in Pennsylvania over Trump-endorsed celebrity doctor Mehmet Oz.

South Carolina Senator Lindsey Graham, a top Trump ally, bluntly conceded to NBC that the election is “definitely not a Republican wave, that’s for darn sure.”

“Never underestimate how much Team Biden is underestimated,” White House chief of staff Ronald Klain tweeted.

A Republican-held House could still derail Biden’s agenda, launching investigations, scuttling his ambitions on climate change and scrutinising the billions of US dollars spent to assist Ukraine in fighting Russia.

The president’s party has traditionally lost seats in midterm elections, and with Biden’s ratings stuck in the low 40s and Republicans pounding him over inflation and crime, pundits had predicted a drubbing.

That would have raised tough questions on whether America’s oldest-ever commander-in-chief, who turns 80 this month, should run again.

Instead, Biden stands to emerge in much better shape than either of his Democratic predecessors, Barack Obama or Bill Clinton, who both took a hammering at the midterms.

DeSantis romps to victory

Democrats need two more wins to hold the Senate. Republicans need two to flip it.

Wisconsin’s incumbent Republican Senator Ron Johnson was declared the winner on Wednesday, but counting the remaining votes in Senate races in Arizona and Nevada could take days.

Georgia is to hold a run-off on December 6 after neither candidate crossed the 50 per cent threshold needed for victory in the Senate race there.

On a night of close contests, one of the most decisive wins was for Florida’s Ron DeSantis, who has railed against Covid-19 mitigation measures and transgender rights and emerged as the main 2024 party rival to Trump.

“I have only begun to fight,” the 44-year-old DeSantis told a noisy victory party.

Trump, who faces criminal probes overtaking top secret documents from the White House and trying to overturn the 2020 election, has not yet formally entered the 2024 presidential fray, but has announced plans to make a major announcement on November 15.

Ahead of polling day, Biden had warned that Republicans pose a dire threat to democracy, calling out their growing embrace of voter conspiracy theories that fuelled last year’s storming of the Capitol.