Labour’s poll gains continued in two surveys published on Thursday. Jeremy Corbyn’s party hit its highest vote share with any pollster since October 2014 in a YouGov/Times poll conducted on Wednesday and Thursday, reducing the Conservative lead to 5 percentage points from 9 points.
Another poll by Kantar Public, conducted after the Conservative manifesto launch before the Manchester bombing, put the gap at 8 points.
Theresa May’s personal ratings also declined, consistent with an impact from her U-turn on social care, though arguably a more limited one than might be suggested by the top-line voting intention numbers. Forty-five per cent told YouGov that Mrs May would make the best prime minister in a head-to-head matchup with Jeremy Corbyn, down from about 50 per cent a month ago.
The larger move is the improvement for the Labour party and its leader. Twenty-eight per cent chose Mr Corbyn as best prime minister — the highest to date — compared with figures consistently below 20 per cent until this month.
On other leadership measures, the prime minister maintains a considerable lead over the leader of the opposition, though her advantage has been reduced considerably during the campaign.
All of this is good news for Labour. Yet there remain questions around the composition of the party’s polling improvement.
Labour is relying to a greater extent than normal on historically unreliable voter demographics. Kantar’s website noted the party has a lot of support from people who did not vote in 2015.
Its support has also increased disproportionately among younger age groups. This poses two risks: not only may young people telling pollsters they will vote fail to do so, but additionally poll samples have a chronic difficulty in reaching youngsters representative of their age group.
There is also a risk that a popular vote surge for Labour may not happen in the places it is needed.
For example, YouGov’s poll has the Green Party on 1 per cent, down from almost 4 per cent in 2015, much of which will be to Labour’s benefit.
However, the Green share in Labour’s marginal seats is lower than elsewhere, so Labour may be gaining votes without gaining or saving as many seats as an even swing would imply.
In any case, it seems clear that 2017 will test to the limit the theory that campaigns do not materially affect the outcome.
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