The data points to a 7% CON to LAB swing since GE2019 in the “Red Wall”
The polling expert and former President of YouGov, Peter Kellner, has an article in the latest New European based on his study of the data from the last four weeks of Opinium polls. Unlike most other pollsters this firm has a range of cross tabs that make such an analysis possible. These include vote splits in the seats gained by CON from LAB at GE2019 as well on those seats gained by Johnson’s party over the last decade.
Each poll subset on its own has such a high margin of error to make analysis like this very difficult. So Kellner has aggregated the splits from the last four polls. This is his main conclusion:
If we apply a seven-point swing to the 54 seats that the Tories gained from Labour, then 45 of them would now revert to Labour. That is not all. Opinium also reports an above-average swing in other seats that the Tories gained from Labour in the previous decade. Twenty five of them would fall to Labour, bringing the total to 70. This would reduce the number of Tory MPs to 295, while Labour would climb to 272. Changes in the fortunes of the Liberal Democrats (11 seats last December) and SNP (48) might affects these figures a little, but probably not much. In reality, even if Opinium’s data is absolutely right, swings will vary from seat to seat. But the chances are that these would broadly cancel out. The Tories would save some seats on a below-average red-wall swing – but lose others on an above average swing.
This is, of course all theoretical and the chances are that there won’t be a general election until May 2024 but it is a reminder that different groups of seats can often see very different voting behaviour.
I think that the big thing here was the disproportionate impact of Corbyn on the LAB vote in the red wall seats. All the evidence at the time was that him being LAB leader was the main reason for so much of the switching. Corbyn is now history and we have a very different ball game.