Mr McCain, who will today hold last-minute rallies in seven swing states in a rapid coast-to-coast dash, remained defiant, insisting that opinion polls had misread the mood of the country. Yesterday, Gallup showed Mr Obama with a 10-point lead over Mr McCain, enough to push him well into landslide territory.

The last time polls briefly recorded Mr McCain in the lead were in September before the financial meltdown. Republican pundits, many of whom have been predicting disaster for weeks, said there was little hope Mr McCain could turn the situation around.

Forecasters were also anticipating a record high turn-out tomorrow based on the unprecedented surge in early voting in states such as Florida and Nevada, where almost half of all voters have voted early and where Democrats have seen a surge in registration, particularly among African-Americans.