Poll sensation: Britain will be an anti-Brexit country by January 2019

Crossover Day – when the Leave majority will disappear, even if not a single voter changes their mind about Brexit – will now be in January, according to a sensational YouGov poll.

Peter Kellner, the former president of the polling firm, said the Leave majority was now declining by 1,350 a day, due solely to demographic changes – older, mainly Leave, voters dying, while teenagers, who are mainly Remain, reach voting age.

He said he now expected Crossover Day to be January 19, plus or minus a few weeks.

He said: “It is now highly likely that if Brexit goes ahead on March 29, it will be on the basis that – again, assuming that not a single voter has changed their mind – a majority of voters would back Remain.”

Writing on the Independent, he said: “Early next year, Britain will switch from a pro-Brexit to an anti-Brexit country.

“To be more precise: if not a single voter in the referendum two years ago changes their mind, enough mainly Leave voters will have died, and enough mainly Remain voters will have reached voting age, to wipe out the Leave majority achieved in June 2016.”

He said that was the clear conclusion from a new YouGov survey for the People’s Vote Campaign, which shows that demographic factors alone are causing the Leave majority to shrink by around 1,350 per day, or almost half a million a year.

Crossover Day, when Remain moves into the lead, will be January 19. By March 29, the day the UK is due to leave the European Union, the Remain majority will by almost 100,000 – again, assuming that nobody who voted two years ago has changed their mind.

Mr Kellner said: “This means that by March 29, it will be difficult to sustain the view that the settled view of the British electorate is that Brexit should take place. We are told that we should ‘respect the verdict of the people’, and not reopen the decision they – we – reached in 2016.

“The latest research shows that this depends not only on the proposition that voters cannot change their minds, but on a specific definition of ‘the people’. It includes those who have died since the referendum – and excludes almost two million new voters who were too young in 2016 but will be old enough to vote by next March.”

YouGov also found that young voters are especially keen on a “new popular vote”, Mr Kellner said.

“Those too young to take part in the last referendum divide three-to-one in favour,” he said.

“Among those who say they would definitely vote, the margin is more than four-to-one. These figures are not surprising but they are significant. We can debate the wisdom of allowing those who were old enough to vote last time to have second thoughts.

“New voters, however, are not requesting the right to have second thoughts; they want their first chance to take part in a decision that could affect the rest of their lives.”