Referendum Danger Zone
By Tom Mludzinski, Director of Political Polling

A win is not always a win when it comes to referendums. While the motivation may often be to settle a debate – at least for the considerable future – they do open up the possibility of simply energising the opposition and giving them momentum, even if they ultimately lose.

The precise parameters depend on where you’re coming from. For example, in 1997 Wales voted by the tiniest margin (50.3% to 49.7%) in favour of establishing a national assembly. That was all the establishment-backed change option needed to win and implement the change, and Wales has not looked backed since.

However, where the establishment is backing the status quo option it needs a comfortable victory (60% or more) to firmly nail the hammer in the opposition’s coffin. See the 2011 AV referendum as a case in point. The Prime Minister and his party backed the status quo (No to AV) and won by a margin of 67% to 33%, thus ensuring that AV is now completely off the agenda while also setting back calls for further electoral reform.

Anything less than a 60%-40% (20 points) victory and the change option can draw comfort and inspiration to keep the fight alive.

The table below shows some typical thresholds for a conclusive win, a conclusive loss, or the Danger Zone. The clearest example of the Danger Zone is the Scottish Independence referendum. The establishment side (Better Together) won, but only on 55% of the vote while the insurgency side (Yes Scotland) secured 45%.


The Better Together campaign really needed a more resounding victory (60% of the vote or more) to ensure the debate of Scottish independence was put to bed for at least a generation. With a margin of just 10 points the Yes campaign are perhaps more energised than even before the referendum.

The direction of travel over the course of a referendum campaign is also an important factor in creating the Danger Zone. If the losing side makes considerable progress over the course of a referendum campaign (e.g. Scottish independence referendum 2014) then this will tend to strengthen their resolve in spite of the loss, and thus increases the likelihood that the debate continues post-referendum.

However, if the losing side loses ground over the course of the campaign (e.g. AV referendum 2011), then it is much harder to motivate the organisations and political actors involved post-referendum, so the likelihood of a follow-up campaign is very low.


David Cameron has called three national referendums in his time as Prime Minister. As well as a party (and Coalition partner) management tool, he has used referendums as a way of trying to put to bed three challenging and recurring issues: electoral reform, Scottish independence and the European Union. His hope has been to end the clamour for change by quashing it directly at the hands of the electorate. However, it is Mr Cameron’s use of the referendum in particular that really risks the Danger Zone which, rather than killing off the debate risks fanning the flames further.

On the face of it David Cameron has an impressive record on referendums: currently two wins from two. The victory in Scotland though was firmly in the Danger Zone, not ending the debate but merely guaranteeing it a top spot on the agenda for the foreseeable future.

It is unusual for a western government to hold a referendum when it would prefer to maintain the status quo1. The Alternative Vote (AV) referendum of 2011, the Scottish Independence referendum of 2014, and now the forthcoming EU referendum have all pitted David Cameron against the change on offer.

Each of the three referendums Mr Cameron has offered have been designed to kill off a thorny problem. His assumption in each case has been that the vocal advocates of a measure (electoral reform, an independent Scotland, Brexit) are misguided in their expectations. The Camerendum is a pragmatic politician’s poker move: a big call on the river. “I’m fed up of your bluff and bluster. You think your hand is stronger than mine? Show me your cards.

Cameron’s Danger Zone

Our research into establishment-backed status quo campaigns worldwide (full report here) shows that the rules are slightly different in Camerendum style plebiscites.There is a Danger Zone – a result where the winning campaign nonetheless fails in its principal objective of ending the debate. Simply “winning” the EU referendum – presuming the Prime Minister will back the Remain option – will not be enough. If he is really to kill off eurosceptic calls to leave the European Union, he will need a resounding victory with at least 60% of the vote. Any smaller margin of the victory and the Leave side will likely be galvanised and not slip away quietly, in the same way the SNP have gone from strength to strength despite losing the referendum last year.