On the surface of it, David Cameron's announcement that the UK would hold a referendum on EU membership in 2015 may come as a shock.
However, if you take voter intention polling data from the last few years from YouGov (pdf), compare Cameron's Conservatives to their rivals to the left, Labour, and their Eurosceptic rivals, Nigel Farage's UKIP, it all begins to make a bit more sense.
If this really is Cameron's plan to win back UKIP voters and Conservative party defectors, however, it may be flawed: despite Farage and others making a big noise about the EU, most polls show that few British voters actually give a damn about Europe.
Amazingly, that even applies even to UKIP voters. UK Polling Report writes that "UKIP support is not particularly connected with Europe, it is an anti-immigration vote and protest vote against some aspects of modern Britain, a general reactionary vote in support of taking Britain back to a status quo ante."