Channel 4 have a useful guide. It seems that Cameron remains Prime Minister, unless Labour were to get an absolute majority, which is highly unlikely. The new fixed-term rules would allow him to hang on and attempt a Queens Speech, where presumably he’d be defeated. Yet he could still hang on until defeated by a Vote of Confidence.
If the Tories have the largest number of seats, and maybe also the largest number of votes, he might try this. He’d be a fool to do so since it would undermine faith in the system, and the opposition parties might do something drastic like boycotting the Queen’s Speech, all of which would discredit traditions. But he’s been a fool before so why not again?
There is also the question of whether Ed Milliband could win a Vote of Confidence. And the interesting suggestion that the Liberal Democrats might demand and get another shot at Electoral Reform. One story is that a major Trade Union is suggesting it, . It could simply be enacted without trying another referendum, which would likely be lost. The interesting thing is, UKIP would also like it.
Polls close at 10 and the first result is likely to be at 10:45. More importantly, when the polls close, people can report Exit Polls. There is likely to be a lot of tactical voting: people voting for their second choice if their favoured party is obviously not going to win in their constituency.