UK election 2015 results: When will Nigel Farage, Nick Clegg, Danny Alexander and Jim Murphy possibly lose their campaigns?

Various polls have suggested that Nick Clegg is set to lose his seat in Sheffield Hallam, while Nigel Farage may miss out on his Thanet South constituency

It's predicted to be the closest general election in decades.

Read The Independent's Election 2015 live blog

650 constituencies will be declared through the night, and every seat will count.

But which seats are set to cause the biggest upsets?

Nick Clegg – Sheffield Hallam

When will we know? - 4.30am

Various polls have suggested that Nick Clegg is set to lose his seat in Sheffield Hallam, despite closing the gap on his Labour opponent Oliver Coppard in the past month. Clegg won his seat in 2010 with a huge majority of more than 15,000, and has been insisting that private Lib Dem polling puts him "firmly ahead", although most polls have only given him a narrow lead.

Nigel Farage – Thanet South

When will we know? - 6am

Farage promised he would step down from his position as Ukip party leader if he loses his seat in South Thanet. Formerly the favourite to win that seat, the chances of him succeeding have looked increasingly slim as the election closes, despite some election experts predicting he had it in the bag as recently as March. A succession of opinion polls placed him behind his Tory challenger Craig Mackinlay.

Jim Murphy: East Renfrewshire

(Andy Buchanan | AFP | Getty Images)

When will we know? - 3am

It’s not looking too good for Scottish Labour leader Jim Murphy, as his party is predicted to lose scores of MPs in Scotland after a big surge in SNP support following the independence referendum.

Murphy, who was only elected as party leader last year, trailed nine points behind the nationalists in his own constituency in several polls, after being 20 points ahead of his closest challenger – Conservative candidate Richard Cook – in 2010.

Danny Alexander – Inverness, Nairn, Badenoch and Strathspey

(AFP/Getty Images)

When will we know? - 5am

The constituency held by Danny Alexander since 2005 is the fourth largest in terms of area. It covers 1,912 square miles, including Loch Ness and the Cairngorms National Park, and boasts 79,000 voters.

Despite this long-lasting hold over the territory, 2015 polls suggest that SNP challenger Drew Hendry could snatch it from under Alexander’s nose, while other competition comes from Tory Edward Mountain, Labour candidate Mike Robb, and Les Durance of Ukip.

Charles Kennedy – Ross, Skye and Lochaber

When will we know? - 7am

The former Lib Dem leader didn't have the best time of it in the lead up to the 2015 election, including a troubling appearance on Question Time.

Various polls put him at risk of losing out to the SNP, with one placing Scottish nationalist Ian Blackford five points ahead of him, on 35 per cent.

Caroline Lucas – Brighton, Pavilion

The Green Party's Caroline Lucas is defending the Brighton Pavilion seat (Getty Images)

When will we know? - 5am

Lucas has remained confident of retaining her Brighton seat, and is likely to have been grateful for a surprise backing from former anti-voter Russell Brand.

Lucas was elected as Britain's first Green Party MP in the seat of Brighton Pavilion at the 2010 election, and has previously said it would cause huge damage for the party’s progress if she fails to be re-elected this year.

She is facing off competition from candidates including Lib Dem Chris Bower, Labour’s Purna Sen, and Tory Clarence Mitchell.