David Cameron faces plunge in support for staying in EU

The referendum battle over Europe has tightened dramatically, according to an exclusive poll that suggests David Cameron needs to restore key powers to Westminster and curb migration if he is to persuade large numbers of sceptics to switch sides.

If the referendum was held today, 57 per cent of those who have reached a view would vote to stay in the European Union, while 43 per cent would vote to leave, found the Ipsos MORI survey for the Evening Standard.

The 14-point lead to stay will be cold comfort for Mr Cameron because it marks a narrowing of the gap since June, when the lead was 69-31.

Around half of those polled said they could be persuaded to change their minds. Only 29 per cent of Britons felt “strongly” about staying in the EU, and 13 per cent strongly wanted to leave.

Two thirds of “outers” said they might change their minds if they thought it would be better for Britain, compared with just over half of “stayers”.

Ipsos MORI also tested the potency of some key reform measures that have been floated by Mr Cameron. The most popular idea was returning more powers to Westminster, such as the right to decide doctors’ hours. Some 32 per cent of out supporters said they would be more likely to vote to stay in the EU if the PM secured such powers.

Restricting free movement within the EU so that migration could be better controlled could persuade 31 per cent of outers to change their minds, while curbing access to benefits for EU migrants could persuade 28 per cent to switch from out to stay.

However, an opt-out from the EU’s founding tenet of “ever-closer union” — seen by ministers as a more easily achievable goal — resulted in only 16 per cent of outers saying they would be more likely to vote stay. Only 19 per cent of outers said they would be more likely to vote stay if there were rules to stop eurozone countries imposing red tape on Britain.