The key battleground states
All eyes have been on Pennsylvania this morning, with its election-winning 20 electoral votes. But let's have a look at the situation in the other battleground states where counting is continuing.
Georgia (16 electoral votes)
Alongside Pennsylvania, Georgia is the other key state that has recently flipped to a Joe Biden lead after a showing a "red wave" early on.
There are currently less than 2,000 votes separating the two candidates, of 4.9 million votes reported. Let me repeat that: it's coming down to less than 2,000 ballots in a state where about 5 million people voted. Talk about a nail-biter.
Nearly all the votes have now been tallied, but because of the tiny margin, there will be a recount.
But even a small Democrat lead is surprising in the Republican stronghold - Donald Trump took the state by five percentage points in 2016 and no Democrat has won there since 1992.
Arizona (11 electoral votes)
Oh boy, results in the Arizona have been quite the rollercoaster. Shortly after polls closed on Wednesday, some major US media outlets, including the AP, were quick to call the state for Mr Biden after he showed a surprising, but convincing, lead early on.
But since then, the lead has steadily narrowed putting the state back into contention.
At present, there is less than one percentage point separating Mr Biden and President Trump, with the Democratic challenger ahead by just over 40,000 votes. More results from Arizona are expected later today.
Another Republican stronghold, if Mr Biden's lead holds he will be the first Democratic presidential candidate to win the state since 1996.
Nevada (six electoral votes)
Mr Biden has long held a narrow lead in Nevada, but after a recent update from Clark County - home to Las Vegas - it's grown to more than 20,000 votes.
The next dump of results is expected later this day, which will be made up of mail-in and provisional ballots. About 93 per cent of votes have been counted so far.
Unlike the above states, Democrat Hillary Clinton won Nevada in 2016 by a small margin.
North Carolina (15 electoral votes)
Mr Trump is ahead in North Carolina by about 1.5 percentage points, a lead that is expected to hold. He won the Republican-leaning state in 2016.
But mail-in ballots are accepted in this state until 12 November, meaning final results will not be available for many days to come.
Mr Biden does not require North Carolina to win the election, but it is crucial for Mr Trump's reelection chances.
A more obvious path to victory for Mr Biden is either a win in Pennsylvania OR some combination of Georgia/Arizona/Nevada.