The Conservatives are set to remain the largest party according to the first exit poll.
David Cameron’s party is set to increase its seats but remain short of a majority.
And the SNP are expected to dominate in Scotland.
The Tories are defending 302 seats, Labour 256 and the Lib Dems 56. But the exit polls suggest neither Labour nor the Tories will get the 323 MPs needed to form a Government.
Labour is confident of making at least 30 gains from the Tories and Lib Dems in England and Wales but there are fears these could be wiped out by the loses to the SNP in Scotland.
Labour has 41 seats north of the border and is battling to stop a tartan bloodbath at the hands of Nicola Sturgeon’s nationalists.
The party’s hopes are pinned on Tories and Lib Dems voting tactically to stop an SNP trouncing.
If no clear winner emerges once all the votes are counted the parties are braced for days, if not weeks, of frenzied coalition negotiations.
The Cabinet manual – the official guide to Parliamentary rules – says the leader with the largest number of MPs gets the chance to form the next government. If he should fail, then the leader of the next largest party is offered the chance.
Labour insiders said Mr Miliband will be quick out of the traps today (FRI) to put Labour’s case should the result remain deadlocked.