Road to the ballot box
DeHavilland has been tracking the overall findings of the UK’s major pollsters throughout the election period.
The graph above shows the trends in the polls for the major political parties from the time of the last General Election up until 2 June 2017. The reference lines show the vote share Labour and the Conservatives achieved at the last General Election, with key events highlighted on the graph. The 2017 General Election campaign period is highlighted in grey.
The polls have almost always shown a Conservative lead, with the brief exception of the period leading up to and around the referendum on the European Union. Labour’s vote share was relatively stable throughout the pre-referendum era, and did not appear to decline significantly after the election of Jeremy Corbyn as Leader.
Following the referendum, the Conservative lead in the polls increased dramatically. Though this was accompanied by a fall in Labour support, most of the Conservative poll boost appears to have been the result of a near collapse in support for UKIP.
It is also possible that some Labour supporters actually went to the Liberal Democrats, whose anti-Brexit stance may have given them a minor bump in the polls. However, it does seem that claims of a “Lib Dem fightback” may have been premature given the party’s subsequent decline in the polls during the General Election campaign.
The gap between the two main parties was biggest at the time the General Election was announced. However, Labour has seen a rapid rise through the polls, with the party now polling over ten points higher than was the case when the General Election was first called
Though this initially appeared largely to the detriment of the smaller parties like the Liberal Democrats and the Greens, recent weeks have seen Labour take votes from the Conservatives as well.
The state of the polls entering the final days of the campaign is largely one of confusion, with different pollsters suggesting wildly varying leads for the Conservative Party.
On the one hand are pollsters like YouGov and Survation, pointing to a relatively narrow lead of under five points. This is a significant number, because the British Polling Council suggests a lead of only five points in a single poll ahead of a General Election is the equivalent of dead heat once margins of error are taken into consideration. Indeed, Survation’s latest poll suggested the Conservatives held a lead of only a single point.
Meanwhile, a ComRes poll over the weekend suggested a lead of 12 points for the Conservative Party – a dip from the peak in support for the party, but more than enough to secure a landslide victory.
Most pollsters suggest a narrower lead of between five and ten points. However, with polling day around the corner it does not seem that the polling companies are able to agree on the state of play going into the General Election.
May on the line
While in most elections the mere fact of all pollsters pointing to a clear lead would be adequate, this General Election is different. Having been called with the explicit purpose of vindicating the Conservative plans for the future, it is essential for Prime Minister Theresa May that she secures not only victory, but a substantial majority. If not, a Conservative majority may prove to be a Pyrrhic victory.
With such wide variations between the pollsters, it seems unlikely that political prognosticators will be able to rely on them too heavily ahead of the big day – despite the excitements of headline poll results such as YouGov’s ElectionCentre seat projections estimate, which indicated a strong possibility of a hung Parliament.
What is certain is that the reputation of pollsters is on the line after they were seen to have failed at the 2015 General Election and the EU referendum. Given the disagreement between polling companies, at least one is going to be red-faced come Friday morning.
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Madhav Bakshi is a Political Analyst within DeHavilland’s Editorial Team and leads on Energy policy. He is a graduate of King’s College London, where he studied International Politics.