YouGov’s latest tracking poll was published overnight, and it put Labour’s lead back at 1 per cent, as most polls have in the past month.
On Monday three polls put Labour ahead 5, 5 and 4 points. For a month very few polls had put Labour’s lead higher than 3. Most showed a tied race or 1-point Labour lead. YouGov had started to even show some Tory leads, but they joined Ashcroft and Populus, who gave Labour a 5-point lead, with a 4-point lead on Monday night.
But Labour’s vote share had scarcely moved. We suggested that their sudden lead was the consequence of a 2 per cent Tory-to-Ukip swing, in the wake of the Rochester by-election. That seems to have been borne out by today’s poll, which shows a 2 per cent swing back to the Tories from Ukip. The publicity spike the latter won over the weekend seems to have faded – and Labour’s sudden lead has faded along with it.
The graph below shows how this week’s polls compare with the 49 published since October 23 (a month ago on Monday).