We shouldn't have been surprised, but it still came as a shock.

In his late-night address from the East Room of the White House, Donald Trump listed the states he had won as supporters cheered.

He was perfectly entitled to do that.

He had not been swept away by a 'blue wave' of support for Joe Biden as many had predicted.

He had a good night, until he decided to address the nation.

Donald Trump claimed there was fraud and that he would go to the Supreme Court to stop the voting.

There are two big problems with his plan.

First off, there is no voting, only counting, and secondly, the courts have already ruled that states such as Pennsylvania are entitled to count votes for days to come.

The US President has claimed for months, without evidence, that mail-in ballots would lead to fraud and inaccuracies.

He has warned that delays in counting votes would result in cheating and he has suggested that he may not accept the result and challenge it in court.

When I speak to Donald Trump supporters, they tell me they like the fact that he does what he says and keeps his promises. His base will no doubt be pleased that he is following through with his threat of legal action.

Other Republicans may not be so happy, however, with some senior members of the party expressing concerns about the president's stance.

I have been covering Donald Trump press conferences for three years. I've listened to him side with Russia over his own intelligence agencies, I've watched him have protesters cleared from outside the White House so he could pose photos and now I've seen him threaten legal action to stop the counting of votes.

Donald Trump could yet legitimately win Election 2020 and retain the White House for another four years. If he does not, a long and uncertain road lies ahead.