Back in the mid-1980s, when Britain was contemplating what assurances to give immigrants from Hong Kong after the handover to China, my elderly next door neighbour, Mrs Stilling, expressed her concern.

In the classic teen movie Animal House there comes a moment when the ne'er-do-well students of the Delta fraternity finally realise their pranks have gone too far. Faced with expulsion from university, the most violent, antisocial drunkard of the group, Bluto Blutarsky (John Belushi), gives one last rousing, rambling speech to his crestfallen comrades. "Nothing is over until we decide it is," he yells. "Was it over when the Germans bombed Pearl Harbor? Hell, no!"

In a period of extreme economic volatility, 2010 was supposed to hold some electoral certainties. To the extent that elections in Western democracies are about choices–a debatable proposition–the decision had been made before a single ballot was cast. This was the conservatives’ year. Every mainstream pundit called it; every poll confirmed it. The vote would be a mere formality. The debate, such as it was, revolved not around the likelihood of a right-wing victory but the scale of the liberal defeat. As winter turned to spring, however, new possibilities sprouted, and the electoral landscape was drastically transformed. By Easter, center-left fortunes had risen from the dead. By the time Passover had come and gone, conventional wisdom had rarely seemed less wise.