Brexit campaigners have been boosted by a new poll giving the Leave camp a 10-point lead.
The survey by ORB for The Independent put the scores at 55 per cent to 45 per cent in favour of pulling out of the European Union, after allowing for an individual's likelihood to vote.
That is a four-point jump in support from April when Vote Leave led by 51 to 49 and an exact reversal of the position when the series of surveys began a year ago.
A 56 per cent majority of 2015 Labour voters — seen as pivotal to the result — back continued membership but 44 per cent are pro-Brexit — while Tories are 62 per cent to 38 per cent in favour of divorce from Brussels.
Scotland was the only part of the UK where a majority said they were in favour of staying in.
Among all voters, Remain is behind by 47 per cent to 53 per cent.
ORB polled 2,000 people on Wednesday and Thursday.