Contrasting figures in Sunday's polls

Yesterday I said I hoped we would get some voting intention polls that would help us judge how the PBR had actually gone down. Today we have no fewer than 3 new voting intention polls, but are none the wiser as to what effect the PBR had on Labour support as they directly contradict each other!

BPIX in the Mail on Sunday has figures of CON 41%(-2), LAB 30%(+1), LDEM 17%(+1) (a narrowing of the Tory lead there - but the changes are from a BPIX poll way back in October, so we can't ascribe it to a PBR effect - just in line with the general narrowing of the lead over the last couple of months)

YouGov in the Sunday Times has topline figures of CON 40%(nc), LAB 31%(+4), LDEM 16%(-2). Changes are from YouGov's poll just before the PBR, so taken alone that would suggest it has given Labour a boost.

However, ComRes in the Independent on Sunday has topline figures of CON 41%(+4), LAB 24%(-3), LDEM 21%(+1). Changes are from their poll at the very end of November. Taking their figures alone, the PBR would appear to have been disasterous for Labour.

The question I'm sure you'll be asking is who is right? Has the PBR sent Labour craashing back into the low 20s, or pushed them back in the 30s? ComRes's poll was conducted one day earlier than YouGov's, but it's not realistic to think there was such a huge shift in support between Thursday and Friday (especially since the press coverage at the time was hardly glowing for Labour). Overall the figures for Conservative support are very similar, the difference is all down to the division between Liberal Democrat and Labour support. YouGov do tend to show the lowest level of Lib Dem support, so that perhaps explains a little of the gap, but does nothing to explain the different direction of travel. I guess we are just going to have to wait for some more polling to see what the dominant trend is.