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With just days to go until local election day on May 2 2024, it appears that the London mayoral race may be narrowing.
Our new poll suggests that the incumbent, Sadiq Khan, now leads his chief rival, the Conservative candidate Susan Hall, by just 13 percentage points. Commissioned by the Mile End Institute at Queen Mary University of London (where I work) and fielded by Savanta from April 8 to 17, the poll was based on a demographically and politically representative sample of 1,038 adults living in London.
The poll finds that if the election were to be held tomorrow, 46% of the vote would go to the Labour Party candidate (Khan) and 33% to Hall. There would be a tight race for third place between the Liberal Democrat candidate (Rob Blackie), on 9% of the vote, and the Green Party candidate (Zoe Garbett), on 7%.
This 13-point lead is significantly lower than the 20-or-so-point leads Khan commanded in polls conducted through March and early April.
The poll narrowing may be genuine but it may also be related to changes in polling methodology. Savanta has introduced a new weighting method for London mayoral polls, designed to correct for the over-representation of 2021 Khan voters and the under-representation of those who supported his Conservative rival Shaun Bailey in 2021 in samples.
This new method first took effect in the April 2024 Mile End Institute poll, and helps to explain why Savanta’s Khan lead shrunk from 24 points in polling conducted with Centre for London in early April, to just 13 points in our poll, conducted later that month.
In polls where methodology has remained consistent, though, Khan’s lead has also narrowed slightly. For example, YouGov’s most recent London mayoral vote intention poll, fielded between April 9 and 17, showed Khan leading Hall by 19 points, while YouGov’s February 2024 Mile End Institute poll had Khan’s lead at 25 points.
Decisive issues and potential vulnerabilities
Boroughs in the south and west of the capital may be key battlegrounds ahead of Thursday. There, Khan leads Hall by just eight percentage points. In the north and east, by contrast, his position is relatively more secure, amounting to no less than a 17 percentage point-lead on Hall.
It is important to note, though, that our sub-sample sizes are quite small in some of our borough groupings. This finding should thus be interpreted with some caution.
This potential narrowing of the polls – and the prospect of relatively strong support for her campaign in south and west London – might be cause for optimism for Hall. However, a greater proportion of Londoners believe that Khan is responsible, inspiring, decisive, competent and ambitious than feel the same way about Hall. And more Londoners believe it is clear what Khan stands for than his rival – though this may just reflect that Khan has already served two terms as mayor.
We found that 77% of Londoners who voted for Khan in 2021 said they would vote for him again if the 2024 mayoral election were to be held tomorrow, while 10% said they would vote for his Conservative rival. A combined total of 9% said they’d switch to Liberal Democrat or Green Party candidates.
In contrast, 85% of the Londoners who voted for Bailey, the 2021 Conservative mayoral candidate, say they would vote Conservative again. Only 5% would switch party by voting for Khan.
When presented with a list of potential issues and asked which were most important when deciding how to vote, respondents said inflation and the cost of living (40%), the NHS (39%), crime (38%), housing (32%) and the economy (31%).
The issue of the expansion of the ultra-low emission zone (Ulez) was not included in the list presented to respondents due to a desire to keep the issue set used consistent across polls, to allow comparison – so we are not able to comment on how the issue of Ulez is likely to shape the vote, on the basis of our data.
It is striking that the issue of the NHS – a policy area over which the mayor of London has little power or influence – appears as though it could have such an impact on the outcome of this contest.
Voting for Hall is motivated by different concerns than voting for Khan, Blackie or Garbett. Among those who said they would vote for Hall if the London mayoral election were tomorrow, the three “most important issues” cited were crime, immigration and the NHS, in that order.
For those who said they would vote for Khan, these were the NHS, inflation and the cost of living and housing.
Those who said they would vote for Blackie, meanwhile, opted for housing, inflation and the cost of living and crime. And those who said they would vote for Garbett chose inflation and the cost of living, crime and the environment and climate change.
Note that prospective Khan and Blackie voters, and Blackie and Garbett voters, have two of their top three vote-motivating issues in common. Hall voters share only one motivating factor of their top three with any of the other voters.
This points to a potential vulnerability for Khan. A vote for Khan appears potentially more readily transferable to the other main candidates than a vote for Hall. Though votes for Hall may transfer, to some extent, to the Reform candidate, Howard Cox.
Elizabeth Simon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
