US President Donald Trump threw the country into a state of uncertainty - and potentially escalated an already fraught election - as he appeared to declare himself the victor while votes were still being counted on Wednesday.
Democratic presidential nominee Joe Biden still has multiple pathways to the White House and, in brief remarks to supporters, said he felt confident he would eventually be declared the winner.
Biden urged patience, as his campaign accused Trump of seeking to run to the courts to have legally cast votes invalidated, in what they described as an affront to the democratic process. Biden's team said it had lawyers ready to fight back.
There was little expectation that a final result would be immediately ready, given the extent of mail-in voting and the sheer number of close races.
Much of the focus, as expected, has turned to Pennsylvania, a key and populous swing state, where Trump's legal team is likely to focus its challenges.
Trump claimed 'major fraud'
The president, known for an aggressive style, often makes strong accusations without sufficient facts, claimed that a "major fraud" was being perpetrated against him by unnamed opponents.
The core of Trump's complaint seems centered on votes that were cast through the US Postal Service, a system he has long railed against, despite it being fully legal and used by tens of millions of people.
Biden has somewhat underperformed the averages of major polls in places like Florida, though key surveys in the final days before the election did predict tight races.