(4) the Scottish independence referendum provoked intense debate both before polling day and since, but there can be little argument that the SNP have surged, to an all-time high in Westminster voting intention, with polls indicating swings in excess of 20% from Labour.
(5) It’s even harder to know what to expect in 2015 when when we’re so uncertain about where we were at the end of 2014. Since the Christmas chaos, Opinium now show Labour just a point ahead rather than 7, with similar numbers from YouGov and Populus. The telephone polls (in particular ICM) will be watched with interest. All of this matters, because many of these larger Labour leads are still included in polling averages.
(6) As has been widely reported, the combined Conservative-Labour share of the vote has declined from the upper 90s in the 1950s to below 60% in some of last year’s polls. As I highlighted here, this is largely explained by a swing from Labour to UKIP.
(Continued…)
