Ipsos MORI show 7% swing in Lab-v-Con marginals

The final round of Ipsos MORI's marginal polling for Reuters has been published. These are polls conducted in Labour held marginal seats where the Conservatives need a swing of between 5% and 9% to win - to win on a uniform swing the Conservatives need a swing of about 6.9%, so this sample excludes around about 60+ of the closest Lab-v-Con marginals, and goes up to seats that would grant the Conservatives a pretty substantial majority. To get a majority of 1, the Conservatives would need to win about half these seats, which equates to being neck and neck in voting intention.

The topline figures from MORI today, with changes from last week, are CON 36%(+1), LAB 36%(-2), LDEM 20%(-1). This represents a slight swing to the Conservatives since a week ago, and with a 7 point swing is just about enough for the Conservatives to get an overall majority on a uniform swing. In practice however, these figures would be unlikely to produce a Tory majority - to win on a 7% swing the Conservatives would also need to gain a substantial number of seats from the Liberal Democrats, and this seems unlikely on present national polling.

There are some interesting findings on tactical voting - MORI asked people if the party they said they were voting for was their first choice, or a tactical choice. 9% said they were voting tactically, a figure which has not risen during the election campaign - despite the widespread and intuitive belief that people make such tactical decisions during the campaign, MORI are not picking it up (or at least, not yet). MORI went on to ask them which party would have been their first choice - there were more people who said their first choice would have been the Lib Dems voting Labour tactically than there were voting Conservative tactically, but the sample sizes are so minute I would not put any weight on it.

Finally, unlike previous waves of the study MORI excluded people who said they were not registered to vote. 5% of the sample said they weren't - I can't see the question in the full tables so I can't tell if these were people who gave voting intentions and were excluded, people who said they were unlikely to vote, or whether MORI asked about registration first and didn't ask unregistered people further voting questions.

UPDATE: Bob Worcester has answered that final question. People were asked if they were registered to vote first, and not asked further questions if they weren't - so we don't know what answers they would have given.

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