As the date of the referendum on UK membership of the European Union approaches, the polls show that support for the Remain and Leave campaigns is still very close. The chart below shows average support for the two sides in more than 200 polls conducted between 2010 and 2016. When we take into account the margin of error associated with surveys the two sides were effectively neck and neck in early May. However, a lot of people continue to be undecided, and if they start to make up their minds as the referendum draws closer, they are likely to decide the outcome.
But who are the undecideds? We can probe this question using a survey of 3,000 people administered at the University of Essex during last year’s general election. At that time 48 per cent approved and 38 per cent disapproved of UK membership, with 15 per cent undecided. The undecideds in the survey were younger (average age 42) but closer in age to the approvers (45) than to disapprovers (53).
As regards occupational status 57 per cent of the high-status group (the ABs) were “approvers”, 33 per cent were “disapprovers” and just under 10 per cent were undecided. In contrast 38 per cent of the low-status group, (DEs), approved, 42 per cent disapproved and 19 per cent were undecided. High-status people are more likely to approve of EU membership and about twice as likely to have decided compared with the low-status group.
Research on the referenda which took place following the Maastricht Treaty in 1992 showed that voters tended to mix up the performance of their own governments with that of the European Union. Thus the unpopularity of the governments in Denmark and France at that time helped to ensure a rejection of the treaty in the former country and near rejection in the latter. This was in sharp contrast to Ireland, which had a popular government and where the referendum passed easily.
The top two issues in the general election of 2015 were the economy and immigration and these strongly influenced attitudes to EU membership. Some 51 per cent who thought that the national economy had improved over the previous year also approved of EU membership, while only 33 per cent who thought that immigration had got worse were approvers. Optimism about the economy and immigration makes people more likely to approve of membership.
Identity has a big influence on attitudes to the EU so that people who identified themselves as solely English in the survey were very different from those who identified themselves as Scottish. Some 33 per cent of the English identifiers approved of EU membership compared with 56 per cent of the Scottish identifiers.
Many people look to the parties to help them decide how to vote in the referendum. When they were asked to rank the party leaders in terms of their likeability, approvers ranked Ed Miliband highest followed by Nick Clegg and David Cameron. Nigel Farage came in fourth place. Disapprovers had the reverse rankings, with Miliband ranked lowest and Farage highest. In contrast the undecideds had the same ranking as the approvers, which implies that undecideds are more likely to listen to political leaders who support UK membership than to those who oppose it.
What can we conclude from this for the vote? First, leavers are less likely to vote than remainers, since lower occupational status is associated with lower turnout in all types of elections. Second, the economy is less buoyant now than at the time of the general election and this should help the Leavers. But economic pessimism has not grown much so this is unlikely to have a big effect.
As for immigration, voters have been pessimistic about this issue for a long time and unless this increases in the next month it is not going to boost support for leaving. Finally all of the party leaders are campaigning to remain except for Nigel Farage. While Boris Johnson and some lesser-known Conservatives are campaigning to leave, it is clear that Remain has a big advantage in the advice stakes. The referendum may be close but it looks like most undecideds who vote are going to opt to remain rather than to leave.
This piece was written by Professor Paul Whiteley, University of Essex. Professor Harold Clarke, University of Texas and Matthew Goodwin, Professor at the University of Kent and senior fellow at the UK in a Changing Europe.