Matthew Goodwin outlines five ways in which it could try to persuade them. Perhaps as much as 42% of the electorate are either unsure about how they will vote in the referendum, or fall into ‘soft Remain’ or ‘soft Leave’ categories. How will the Leave campaign seek to win over these people? Based on British Social Attitudes research released this week,outlines five ways in which it could try to persuade them.

Since David Cameron’s announcement that the referendum will be held on June 23, we have had a few new polls. What is the overall picture? In the Poll of Polls , the headline is Remain on 53% versus Leave on 47%. With 115 days to go, there really is everything to play for.This week we are exploring a different question: what are the most plausible scenarios whereby the Outers win? We hear much about how they are the underdogs, but little about how their campaign could possibly deliver Brexit – based on the research. We now know that a large number of voters are ‘soft’ – people who are leaning toward Remain or Leave, but who readily admit that they could change their minds. In a recent YouGov poll of 4,000 adults it was suggested that as much as 42% of the electorate fell into this category or were Unsure about how they will vote. Much will depend on how successfully the Remain and Leave campaigns convert these voters. After all, the outcome at the referendum in Scotland was determined less by winning over the undecided than convincing Yes voters to switch to No. At a Chatham House briefing this week I outlined six fairly plausible ways that the Outers could win. Here they are…

1. A populist anti-establishment revolt against threats to British identity

The research on Euroscepticism is clear about one thing – the more concerned that somebody is about threats to British identity, the more likely they are to back Brexit. This is reflected in a recent Chatham House briefing paper on the drivers of anti-EU attitudes – those who felt strongly concerned about the economic and cultural effects of immigration were consistently among the most likely to back Brexit. However, the key word is intensity. It is also clear that Brexit is only a majority view among those who feel the most strongly concerned about threats to British identity. Take a look at the table below, taken from the new British Social Attitudes report released this week. The first thing to say is that public anxiety over how the EU is seen to be undermining British identity is widespread. But it is also true that there is only majority support for leaving the EU among those who ‘strongly agree’ that the EU threatens Britain’s identity. Even among those who only ‘agree’ about this threat to identity, Brexit lacks majority support, while those who do not feel culturally threatened back Remain in large numbers. One possible path to Brexit, therefore, is to intensify this public angst over threats to British identity, pushing a larger number of people into the ‘strongly agree’ column. This is where the refugee crisis and net migration are especially important.

2. A populist anti-establishment revolt rooted in Englishness

A different but related path to Brexit is a revolt against Brussels rooted more specifically in appeals to Englishness. This draws on research that shows that there is a very strong association between feelings of English identity and Euroscepticism. Take a look at the chart below, taken from a recent and very large YouGov poll of over 4,000 British adults. People who identify themselves as Leave voters consistently prioritise their Englishness over Britishness, whereas people who identify with Remain prioritise their Britishness over Englishness. Brexiters, therefore, may want to spend the next four months pitching to this English identity. On the other side, David Cameron would be well advised to avoid doing anything that might inadvertently fuel this Englishness (such as by reminding the English that they could free themselves from the Scots by voting for Brexit).

3. Open up a new flank – the National Health Service

There is a neglected but intriguing area in this referendum debate – the National Health Service. When voters were recently asked about the effects of Brexit on different areas of national life, such as Britain’s economy or global influence, the NHS was the one area where people appeared more convinced that Brexit might actually help rather than hinder. Take a look at the chart below, based on YouGov data. This shows the ‘net good’ effect of Brexit on the NHS (i.e. the percentage of voters who think the effect will be good minus the percentage who think it will be bad). First, it is worth noting that the percentage of voters who think Brexit will have a good effect on the NHS is around twice as high as the percentage who think it would have a bad effect. Only the most committed Remain voters think that Brexit would have negative effects, while all other voters appear receptive to the idea that by leaving the EU Britain could invest more resources into its hospitals and improve a public resource going through tough times. ‘Leave the European Union to save the NHS’, appears to be one line that might resonate. That the Leave groups are targeting the NHS suggests that this finding has emerged in their own focus groups – and remember that the NHS is also cherished by the older, working-class voters who lean toward Brexit. This is why, when Labour was trying to contain UKIP last year, they devoted considerable effort to framing Nigel Farage’s party as a Thatcherite movement that wanted to privatise the NHS. Much will depend on whether Eurosceptics seriously go after this issue and how, in turn, the Remain camp respond.

4. Cut through with a new messenger

A fourth way that Outers cross the line is by finding a messenger who can appeal to wavering voters and neutralise the ‘Cameron Effect’. Make no mistake – David Cameron is a major asset for the Remain camp. The prime minister is, with the only exception of diehard Outers, the most trusted political voice in this debate. He will be able to make inroads into the soft Remain and soft Leave voters, and the Undecided, and we also find that Cameron might even help to mobilise middle-aged Labour and Liberal Democrat voters around the Remain flag. The Remain camp clearly know this, which is why Cameron is fronting almost every intervention. Given that Cameron is not an especially unpopular prime minister, this is a major hurdle that the Outers need to overcome. On the one hand they may be helped by the current position of Jeremy Corbyn, who at best appears like a reluctant passenger in the referendum debate. But on the other hand they are clearly going to struggle to reach across to the more moderate and risk averse voters. Finding a messenger who can do this and neutralise Cameron will be key. Boris Johnson playing a central, active and highly prominent role in the campaign is perhaps the only shot that Outers have (unfortunately the poll below did not probe attitudes to Boris). Farage will clearly be important on the Leave side.

5. Play the turnout game

Turnout is likely to be a major factor in Britain’s referendum result. The EU vote is not like the independence referendum in Scotland – there is no major groundswell of public enthusiasm. The issue of the EU has, traditionally, never excited the electorate. This introduces a risk for Remain and a potential advantage for Leave. What if the more pro-EU voters – the financially secure, higher income and university educated middle-classes, and the 18-30 year olds – decide that they simply cannot be bothered to vote? This would contrast sharply to evidence which suggests that the Leave camp’s core followers – white pensioners – will be more determined to register their anti-EU views. At the general election last year it was widely believed that UKIP’s share of the vote would crash as polling day approached. That it remained static reflected the commitment of these diehard Eurosceptics. If Remain finds itself struggling to mobilise the young and financially secure professionals then the Leave camp, with a decent mobilisation strategy, could find itself pushing ahead on polling day.

6. Employ the winning formula

The past week has thrown considerable light on one central question: what pushes somebody from being a Eurosceptic into voting for withdrawal? There are lots of Eurosceptics in Britain – they are a clear majority. But when it comes to the crunch only a smaller number are actually prepared to back Brexit. Why is this? The new British Social Attitudes report has put forward one convincing explanation, suggesting that the Outers need to win two arguments. On the one hand, they need to mobilise the culturally threatened. But on the other they need to win the economic argument. Put it this way, among voters who believe that the EU threatens Britain’s cultural identity AND are convinced that leaving the EU would improve the economy, support for Brexit is over 80%. But among voters who are only won over by the cultural argument but not the economic case, support for Brexit is only 40%. This is where the Outers could fall down – intensifying those cultural arguments, while failing to satisfy people who are more averse to the economic risks of Brexit. To win they will need to make headway on both of these fronts, but especially the latter.

This post represents the views of the author and not those of BrexitVote, nor the LSE.

Matthew Goodwin is Professor of Politics in the School of Politics and International Relations at the University of Kent, and Associate Fellow at Chatham House. He is also a senior fellow at the UK in a Changing Europe project. His most recent book is the co-authored Revolt on the Right: Explaining Support for the Radical Right in Britain (2014). @GoodwinMJ