Ipsos Political Monitor: Aggregated 2009 results

Ipsos has aggregated the voting intention findings from the twelve monthly Political Monitor surveys conducted in 2009, giving a larger sample size that allows for more detailed analysis of the demographic pattern of party support. We will continue to analyse this data over the forthcoming weeks, and it will be used to feed into future commentary and releases.

Over 2009, the Conservatives maintained a comfortable lead over Labour, averaging a 42% share among those certain to vote, compared to Labour's 26% and the Liberal Democrats' 19%.These figures are closely in line with the average of the 128 published polls conducted by all the polling companies in 2009, which found an average share of 41% for the Conservatives, 27% for Labour and 18% for the Liberal Democrats.

Just over half the public, 51%, said they would be absolutely certain to vote in an immediate general election, but Conservative supporters were more likely to be certain to vote (66%) than those supporting Labour (52%) or the Liberal Democrats (59%). It is this turnout advantage that provides much of the Conservative lead: taking the views of all those who expressed a voting intention regardless of their likelihood of voting, the Tories' lead over Labour was only 37% to 30%, with the Liberal Democrats on 19%.

The Conservatives and the Liberal Democrats are both somewhat stronger among women than among men, while Labour conversely is weaker. Men who were certain to vote said they would do so in shares of 40% for the Conservatives, 28% for Labour and 17% for the Liberal Democrats, while women would split 43%, 25% and 20% respectively. The Conservatives are also strongest among older voters, but Labour's strength is much less differentiated by age. In terms of social class, Conservative share is stronger amongst ABC1 voters (44%) than amongst C2DE voters (37%).

Technical details

Ipsos interviewed a representative sample of 12,076 adults aged 18+ across Great Britain. Interviews were conducted by telephone in twelve monthly surveys between January and December 2009, using random digit dialling and quota sampling. Data are weighted to match the profile of the population. Where percentages do not sum to 100, this may be due to computer rounding , the exclusion of 'Don't Know' categories, or multiple answers. Of the sample of 12,076, a total of 6,289 respondents said that they were "absolutely certain to vote" at an immediate general election: "headline" voting intention figures are based only on these respondents.

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