Donald Trump has won the key battleground state of Florida in an extraordinary twist on election day.

Mr Trump desperately needed the state as his route to presidential victory is narrower than his rival, but it has become wider after winning this swing state.

The result, announced around 11pm Eastern Time, is one of the most important results of the election night so far and helps to pave the way to the Oval Office.

As the results poured in for Florida voters, Mr Trump had an early lead. Around 8pm ET, however, Ms Clinton gained the lead of 80,000 votes. Mr Trump then stole back the lead by 11pm.

The winning candidate needs more than 270 electoral votes to win and Florida has 29 votes up for grabs.

Its swing state status means it tends to have no significant support from either party, therefore a win for the Democrats or Republicans is a key victory and a good opportunity to win electoral votes.

It is one of 13 important swing states across the US.

In 2012, it was the last state to be called in the presidential election and was also the closest.

Tampa was the site of the Republican National Convention, but the state ultimately went to president Barack Obama with 50.01 per cent of the vote and 49.13 per cent to Republican Mitt Romney.

Florida was one of the first swing states to close its polls and release the results.

In the senate race, Republican Marco Rubio and former rival to Mr Trump was projected to win.