The Yes and No campaigns in the referendum for Scottish independence land will intensify their push for votes today.
A poll yesterday suggested the Yes campaign has taken the lead for the first time.
That has spooked markets in London this morning - the pound has slumped to a 10 month low.
Michael Hewson, an analyst at CMC Markets, said: "For quite some time investors had dismissed the prospect of a Yes vote as an outlier, but recent opinion polls have shifted that perception and this has been no better demonstrated than by the plunge in sterling this morning."
Uncertainty over the currency that an independent Scotland would use, and the shape and role of its monetary system have dogged markets.
Mr Hewson added: "One thing is certain, if we get this sort of volatility on the prospect of a Yes vote, can you imagine the reaction if we do get a Yes vote? It's not likely to be pretty."
Despite the weekend poll Alistair Darling - who heads up 'Better Together' - is defiant:
