There are many different scenarios and possible results and few hard and fast rules as to what is going to happen if no single party has enough MPs - 325 - to ensure they can win votes even if all other MPs in Parliament vote against them. But the view of constitutional experts, and past precedents is that if this is the case Gordon Brown, as the incumbent prime minister, will have the right to stay on and try to form an administration. This is even if the Conservatives have the most seats. He does not have to go until it is obvious that he does not command the confidence of Parliament - which would mean being defeated on the Queen's Speech vote, or, if he survived that, a subsequent no confidence motion in the Commons. But exactly how events would unfold can only be speculation at this stage, says Dr Ruth Fox, director of the Hansard Society's parliament and government programme