The key states to look out for in tonight's US election

Democrat Hillary Clinton is bidding to become the first ever female tenant of the Oval Office as the US presidential election enters crunch time on Tuesday, with Republican Donald Trump hoping to overcome a string of personal controversies to succeed Barack Obama to become the 45th president of the country. Which states hold the key to victory?

With the United States encompassing six different time zones, results will start filtering in around 00:00 GMT as the first polling stations close in the East Coast. Kentucky and Vermont have traditionally been the first two to declare who wins their set of electoral college votes.

Virginia will be the first key battleground state to declare among this raft of eastern coast states, but it may take hours after stations close.

North Carolina and Ohio are the next major swing states to close at 00:30 GMT, and by the time their counts are in te picture will be much clearer.

At 01:00 GMT a flood of declarations will come, most crucially from Pennsylvania and Florida, the latter of which having a notorious electoral history. If the result is close it may be hours or even days before a winner is called.

As we go through the night more and more states will close their stations, and at around 02:00 GMT the big hitters of Texas and New York.

As we approach 03:00 GMT Utah and Nevada will be among the latest to call a winner, and US television channels will begin itching to announce a winner.

California forms part of the last batch of states with its massive 55 votes, and will come out at 0500 GMT, but it is expected to go in favour of Clinton. At this stage the winner could already be widely known, but tradition dictates the losing candidate will make a concession speech