An exclusive BMG poll, commissioned by the Evening Standard, reveals that around 10% of voters could change their mind about how they will vote in the upcoming EU referendum depending on the views of Boris Johnson.

The poll was conducted over the weekend that Johnson was reportedly considering which campaign to support, but before he announced his intention to support the Leave campaign.

In order to robustly measure the expected ‘Boris Effect’ on the campaign and whether there may be any impact on how UK adults will vote in the upcoming EU referendum, a random subset of respondents during the poll were asked “If Boris Johnson came out in support for the UK leaving the European Union how would you vote?” and these results were compared with a similarly asked question on the survey.

The results reveal that a Boris recommendation to leave the EU would not necessarily lead to direct switching, but instead to more uncertainty. The ‘remain’ share fell by 9% and the proportion of those undecided increased by 10%.

Readers can interrogate the data for themselves by toggling with the drop-down menu in the chart below.

The interim findings found that the ‘effect’ was highest amongst younger voters aged 18-44 and those who say they are not interested in politics indicating Boris Johnson reaches people who are beyond regular politicians.

Dr Michael Turner, Research Director at BMG Research, said “This is a direct effect of Boris. The Mayor is eating directly into the Remain campaign. It is not direct switching, which we would not expect at this stage, but a significant group that had planned to vote Remain that subsequently becomes less sure how they should vote in June. It suggests these people are suspending their verdicts until they hear what he has to say.”

An article based on these polling results, released by the Evening Standard, can be found here.

An article based on these polling results, released by the Daily Express, can be found here.

Data tables containing a breakdown of the results can be found here.

For further details about this poll, and any other results from our polling series, please feel free to get in touch by email or phone.


Dr Michael Turner – Research Director


Lauren Harris – Research Executive



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