The outcome of the US presidential election remained in the balance on Friday as a handful of battleground states complete their vote counts and thousands of ballots are still left to be counted.

Former Vice President and Democrat Joe Biden overtook Republican President Donald Trump in the number of ballots counted in Georgia and Pennsylvania, two must-win states for Trump. Biden now has a 917-vote advantage in Georgia and an over 5,000-vote advantage in Pennsylvania, according to the Associated Press.

As Biden moved closer to winning the White House, Trump adopted a fighting posture, making false claims to undermine a vote that was not going his way.

Biden has racked up at least 264 of the 270 electoral votes that he needs. Donald Trump has amassed 214 electoral votes so far, and is still in contention in several states that would afford the Republican incumbent a path to re-election.

States yet to finalise winner

• Alaska – 3 votes (Trump leading convincingly)

• Nevada – 6 votes (Biden leading with thin margin)

• Pennsylvania – 20 votes (Biden leading with thin margin)

• North Carolina – 15 votes (Trump leading)

• Georgia – 16 votes (Biden leading with thin margin)

Expected to report final vote counts on Thursday night or Friday are Georgia (16 electoral votes), North Carolina (15), and Nevada (6).

However, mail-in ballots sent on or before Election Day in North Carolina can be counted until November 12.

Three days after Election Day, neither candidate had amassed the votes needed to win the White House. But Biden’s victories in the Great Lakes states left him at 264, meaning he was one battleground state away — any would do — from becoming president-elect.

By flipping yet another critical battleground state that Trump won four years ago, Biden placed himself in a comfortable lead, with only 6 electoral votes shy of the presidency.

Biden could reach the magic number to gain the White House with a win in either Georgia, North Carolina and Nevada, if he keeps Arizona. Trump needs to capture all three to stay competitive.

Nevada, where Biden is favoured, could put him precisely at the number needed to win, if he keeps Arizona. With more than 89 per cent of the vote counted, Biden was leading by less than 11,500 votes.

However, Pennsylvania is the biggest prize remaining, with 20 electoral votes. In the battle ground state of Georgia, Biden pulled ahead by 917 votes, according to AP, as counting continued.

Much of the delay has resulted from a flood of mail-in ballots due to the coronavirus pandemic — and those votes have tended to favour Democrats. If Biden's lead in Arizona holds, and he wins Nevada or Georgia, he would pass the threshold of 270 electoral votes.

Should Trump hold North Carolina and Georgia but lose Arizona, he must take Nevada as well as Pennsylvania to win.

Simply winning Pennsylvania — where Biden just pushed ahead in the lead — will not be enough for the president, even if he takes Alaska's three electoral votes as expected.

Much to Trump's chagrin, Pennsylvania has decided to allow mailed ballots sent by Election Day but received up to three days afterwards to be counted. Authorities expect to complete the count by Friday.

Another factor that could keep the battle alive: the Trump campaign has unleashed a legal blitz in key states vital to the incumbent's re-election.

It has sued to disqualify late-arriving ballots in Pennsylvania, sued in Nevada and Georgia over alleged irregularities, and has demanded a recount in Wisconsin.

Michigan

Biden carried Michigan and its 16 electoral votes. The flip from red back to blue was a huge blow to Trump, whose victories in Michigan, Wisconsin and Pennsylvania in 2016 sent him to the White House.

Biden’s campaign had particularly focused on turning out Black voters in Detroit, who failed to show up for Hillary Clinton in the numbers that Barack Obama received during his two presidential bids.

Despite needing to win Michigan, Trump took frequent swipes at the state’s Democratic governor, Gretchen Whitmer, who was the target of an alleged kidnapping plot that was foiled by federal law enforcement. Chants of “Lock her up!” toward Whitmer echoed at Trump’s rally, and he railed against the governor on Twitter for her cautious approach to the coronavirus pandemic.

Wisconsin

Biden defeated President Trump in battleground Wisconsin, securing the state’s 10 electoral votes and reclaiming a key part of the blue wall that slipped away from Democrats four years ago.

The Associated Press called Wisconsin for Biden after election officials in the state said all outstanding ballots had been counted, save for a few hundred in one township and an expected small number of provisional ballots.

Trump’s campaign has requested a recount. Statewide recounts in Wisconsin have historically changed the vote tally by only a few hundred votes; Biden leads by .624 percentage points out of nearly 3.3 million ballots counted.

In 2016, Trump won Wisconsin by fewer than 23,000 votes, a breakthrough that along with wins in Michigan and Pennsylvania helped hand him his first term in the White House. Democrats were determined to reclaim Wisconsin, a state that before Trump hadn’t gone for a Republican since Ronald Reagan in 1984.

Arizona

Democrat Joe Biden won Arizona and its 11 electoral votes, serving a huge blow to Trump’s chances for reelection. Arizona has backed a Democratic presidential candidate only once in the last 72 years.

Biden’s campaign had focused on Arizona as part of its expanded battleground map through the Sun Belt, citing demographic changes, new residents and realignment away from Republicans among key suburban voters.

Arizona is among the more than half a dozen states that will help determine which candidate gets the 270 electoral votes to capture the White House.

Texas

Trump won Texas and its 38 electoral votes despite a furious, late push by Democrats to turn America’s biggest red state blue.

An avalanche of early votes fed Democrats’ high hopes of ending decades of losses in Texas, where polls showed Joe Biden running unusually close. But Trump carried Texas for a second straight year.

Trump won Texas by 9 percentage points in 2016 and all but took a win here for granted. He didn’t swing through Texas for campaign rallies or swamp television airwaves, and his conservative allies on the ground scoffed at Biden’s chances as a far reach.

Florida

Trump also won Florida and its 29 electoral votes, the biggest prize among the perennial battlegrounds and a state crucial to his reelection hopes.

A victory in Florida means re-election is within Trump’s grasp. A loss in the state would have made it nearly impossible for Trump to reach the 270 electoral votes needed to retain the White House.

Maine

President Trump won one of Maine's four electoral votes, just as he did in 2016.

Trump carried the state's 2nd Congressional District, the more rural and conservative of Maine's congressional districts.

While Biden easily carried the state itself, Maine is one of only two states that divide their electoral votes.

Biden won the 1st Congressional District and the statewide tally, good for three electoral votes. Trump's victory in the 2nd Congressional District means he wins one electoral vote.

Results pour in

Biden won California, Oregon and Washington state, while President Donald Trump won Idaho.

California, Oregon and Washington are all liberal states, while Idaho is conservative.

California has 55 electoral votes, the biggest haul of any state. It’s also the home of Biden’s running mate, Senator Kamala Harris. She served as the San Francisco district attorney and the state’s attorney general before winning election to the Senate in 2016.

Trump won Ohio and its 18 electoral votes, holding on to a battleground state where the race against Biden had tightened in recent months.

The Republican nominee comfortably carried the Midwestern state four years ago, but polls heading into the final weeks showed Biden well within range, forcing the president to spend more time in the state than anyone expected.

Trump also won four of Nebraska’s five electoral votes, while Biden won one electoral vote from the state. Biden’s win in the 2nd Congressional District, which includes Omaha, is a flip from 2016, when Trump narrowly won it against Democrat Hillary Clinton.

Early wins

Soon after the polling time ended, AP reported that President Trump had won Kentucky, and Biden had carried Vermont.

There were also some predictable victories for each candidate, with Trump taking Alabama, Mississippi and Oklahoma and Biden winning Massachusetts, his home state of Delaware and Virginia, a former battleground that has become a Democratic stronghold.

Trump also took West Virginia, South Carolina, Tennessee, Arkansas, Indiana, Louisiana, North Dakota, South Dakota and Wyoming.

Meanwhile, Biden won Connecticut, Illinois, Maryland, Massachusetts, New Jersey, Rhode Island, New Mexico, New York, the District of Columbia and Colorado.

Record-setting polling

Voters, many wearing masks and maintaining social distancing to guard against the spread of the coronavirus, experienced long lines in a few locales and short waits in many other places. There were no signs of disruptions or violence at polling sites, as some officials had feared.

The winner — who may not be determined for days — will lead a nation strained by a pandemic that has killed more than 231,000 people and left millions more jobless, racial tensions and political polarisation that has only worsened during a vitriolic campaign.

Control of the Senate is at stake, too: Democrats needed to net three seats if Biden captured the White House to gain control of all of Washington for the first time in a decade. The House was expected to remain under Democratic control.

A new anti-scaling fence was erected around the White House, and in downtowns from New York to Denver to Minneapolis, workers boarded up businesses lest the vote lead to unrest.

With the worst public health crisis in a century still fiercely present, the pandemic — and Trump’s handling of it — was the inescapable focus for 2020.

For Trump, the election stood as a judgment on his four years in office, a term in which he bent Washington to his will, challenged faith in its institutions and changed how America was viewed across the globe.

Rarely trying to unite a country divided along lines of race and class, he has often acted as an insurgent against the government he led while undermining the nation’s scientists, bureaucracy and media.

At the White House on Tuesday night, more than 100 family members, friends, donors and staff were set to watch returns from the East Room.

Trump was watching votes come in upstairs in the residence with a few close aides. Most top campaign officials were monitoring returns from a “war room” set up in the Eisenhower Executive Office Building.

Read: On US election day, Trump says he feels 'very good' about chances

Biden spent the day last-minute campaigning in Scranton, Pennsylvania, where he was born, and in Philadelphia with a couple of local stops in Wilmington, Delaware, where he was spending Election Night.

The president began his day on an upbeat note, predicting that he’d do even better than in 2016. But during a midday visit to his campaign headquarters, he spoke in a gravelly, subdued tone.

“Winning is easy,” Trump told reporters. “Losing is never easy, not for me it’s not.”

Biden, on the other hand, took a more cautious approach. “I’m superstitious about predicting what an outcome’s gonna be until it happens [...] but I’m hopeful,” said Biden. “It’s just so uncertain [...] you can’t think of an election in the recent past where so many states were up for grabs.”

With the coronavirus now surging anew, voters ranked the pandemic and the economy as top concerns in the race between Trump and Biden, according to AP VoteCast, a national survey of the electorate.

Voters were especially likely to call the public health crisis the nation’s most important issue, with the economy following close behind. Fewer named health care, racism, law enforcement, immigration or climate change

The survey found that Trump’s leadership loomed large in voters’ decision-making. Nearly two-thirds of voters said their vote was about Trump — either for him or against him.

The momentum from early voting carried into Election Day, as an energised electorate produced long lines at polling sites throughout the country.

Voters braved worries of the coronavirus, threats of polling place intimidation and expectations of long lines caused by changes to voting systems, but appeared undeterred as turnout appeared it would easily surpass the 139 million ballots cast four years ago.

No major problems arose on Tuesday, outside the typical glitches of a presidential election: Some polling places opened late, robocalls provided false information to voters in Iowa and Michigan, and machines or software malfunctioned in some counties in the battleground states of Ohio, Pennsylvania, Georgia and Texas.

The cybersecurity agency at the Department of Homeland Security said there were no outward signs by midday of any malicious activity.

The record-setting early vote — and legal skirmishing over how it would be counted — drew unsupported allegations of fraud from Trump, who had repeatedly refused to guarantee he would honour the election’s result.

Referendum on Trump

Supporters of both candidates called the election a referendum on Trump and his tumultuous first term. No US president has lost a re-election bid since Republican George H.W. Bush in 1992.

Trump is seeking another term in office after a chaotic four years marked by the coronavirus crisis, an economy battered by pandemic shutdowns, an impeachment drama, inquiries into Russian election interference, US racial tensions and contentious immigration policies.

Biden is looking to win the presidency on his third attempt after a five-decade political career including eight years as vice president under Trump’s predecessor, Barack Obama.

Biden has promised a renewed effort to fight the public health crisis, fix the economy and bridge America’s political divide. The country this year was also shaken by months of protests against racism and police brutality.