The Green Party have just released an ICM poll of Brighton Pavilion that shows them leading the Conservatives by 8 points in the seat with Labour in third place.
Clearly the Greens have commissioned it for their own purposes, and one should always look carefully at polls commissioned by political parties – they aren’t releasing those figures out of the goodness of their hearts – but in this case it appears kosher.
The full figures, with changes from the notional figures at the last electon, are CON 27%(+4), LAB 25%(-13), LDEM 11%(-5), GRN 35%(+14).
I need to add two caveats – firstly the sample size was only 533. Rather counterintuitively, just because you are polling a much smaller population than a poll of the whole country, it makes virtually no difference to the sample size you need for a given margin of error, so the margin of error on the poll once you exclude don’t knows and won’t votes is going to be somewhere in the region of 5 percent.
Secondly, there is the question asked: “Labour, the Conservatives, the Green Party, the Liberal Democrats and other parties will fight a new election in 2010 in your area. If there were a general election tomorrow which party do you think you would vote for?” Normally pollsters do not prompt by minor parties in voting intention questions, while this doesn’t seem very fair, it’s what years of experience suggest gives the most accurate answer. However, here we have a rather unusual situation where a minor party are obviously at least in the running to win the seat given the last general election and their strength on the local council, what’s more local voters are reasonably likely to be aware of it. While including the Greens in the prompt will probably have boosted their support, it would have been perverse not to given the situation in Brighton Pavilon.