ComRes’s monthly online poll for the Independent on Sunday and Sunday Mirror is out and has topline figures of CON 31%, LAB 36%, LDEM 8%, UKIP 14%.
The changes from last month are bit complex. As regular readers will know, there has been a bit of a back and forth in ComRes’s methodology. For most of last year ComRes treated likelihood to vote for minor parties differently to how they did it for the main parties – for the big three they included people who said they were 5/10 or more likely to vote (weighted proportionally), for minor parties they only included those who said they were 10/10 certain to vote. In their December online poll they experimented with treating all parties the same on turnout, producing a substantial jump in UKIP support. In January they used their old method, which dropped UKIP back down by 4 points. Unfortunately this wasn’t flagged up in media reporting of the polls, giving the impression of UKIP increasing in December and then dropping back down in January after Cameron’s EU referendum pledge, when actually much of the movement was due to methodological reasons.
Anyway, the back and forth seems to be behind us – ComRes have now shifted to treating all the parties the same when it comes to taking account of likelihood to vote:
“In recent months we have been exploring the best way to treat smaller parties when calculating voting intention. We have experimented with including smaller parties in voting intention scores only if respondents are certain to vote; this has been on the basis that, comparing polling against actual 2010 results, we were concerned that the traditional method was over-stating smaller parties. However, with UKIP the game has changed and we therefore propose that from now on supporters of smaller parties will be included if respondents are 5/10 or above in terms of likelihood to vote, as is the case with the major parties. We will however continue to review our methodology as the general election approaches”
The effect is simply to increase the reported level of support for minor parties, with the Conservatives, Labour and Liberal Democrats all decreasing proportionally. Last month’s ComRes figures were CON 33%, LAB 39%, LDEM 11%, UKIP 10%, so a naive comparison would suggest a significant increase for UKIP with everyone else suffering. However, ComRes have released changes on what last month’s figures would have been using the new method, implying that last month’s figures would have been CON 32%, LAB 37%, LDEM 11%, UKIP 13% and that today’s poll actually shows very little difference for the Conservatives, Labour or UKIP.
That is interesting in itself – last month’s ComRes poll was the height of the post-referendum boost for David Cameron. Polls since them for other companies have shown whatever benefit Cameron accrued from his referendum boost fading away again, but ComRes have him consolidating it. As ever, that could be a sign of a Conservative advance, but in the absence of other polls confirming it will probably turn out to be a blip.
UPDATE: Full tabs are here