Donald Trump has launched legal challenges in five key US states, alleging that election officials are counting fraudulent votes.
As a result, though Joe Biden has been announced the winner of the election, the process could be protracted for weeks, and the damage to public confidence in the democratic process could last much longer.
On Monday, 9 November, the US Attorney-General instructed prosecutors to investigate claims of voter fraud – though there is little evidence of it. This led to the resignation of justice department official Richard Pilger on the same day.
Here is what’s happening in each state. For the latest election updates, see our live blog.
Which states are facing voting challenges?
The Trump campaign filed a fresh lawsuit in Michigan on Wednesday, 11 November, this time asking a federal court to block the state from certifying the election – which Joe Biden won by around 145,000 votes.
It is alleging there were irregularities in the way in which votes were tabulated and also that Republican observers were improperly harassed.
Allegations include that ineligible ballots were counted including votes which were deposited in dropboxes after the deadline.
The campaign filed a similar claim in a Michigan state court, which was dismissed by the judge, Timothy Kenny, who said he found no evidence to support the assertions.
The state was key to Donald Trump’s victory in 2016, when he flipped it from the Democrats by less than 11,000 votes, but this year Joe Biden has won its 16 electoral votes with 99 per cent of the votes counted.
Mr Biden claimed victory in Georgia, and was the first Democrat to do so for almost three decades.
However, the Republican Secretary of State in Georgia, Brad Raffensperger, has ordered a hand recount of ballots in Georgia, after Mr Biden claimed victory in the state by 14,000 votes.
After the hand recount, the losing party can request another, which would be done by machine in the state which has 16 votes in the Electoral College.
Mr Raffensperger has dismissed claims of election fraud, and cast doubts on the likelihood of the recount swinging the result in Mr Trump’s favour.
He acknowledged there may have been some illegal voting, but said “My office is investigating all of it. Does it rise to the numbers or margin necessary to change the outcome to where President Trump is given Georgia’s electoral votes? That is unlikely.”
A formal recount will take place in late November. However, despite the recount, it now looks impossible for Mr Biden’s lead to be overturned, as the Democrats won the state by an overwhelming majority.
Georgia was a vital state for the president, who would have needed to win more of the remaining states than Mr Biden in order to grab the presidency.