Mainstream Protest Voting: Did Voters Choose Brexit and Corbyn because they expected them to lose?

Abstract

Recent UK elections have seen apparently unexpected levels of support for the Leave side in the EU referendum and the Labour party under Jeremy Corbyn. Some commentators have argued that these surprising results were not driven by actual support for these outcomes, but by voters who did not expect their choice to win. It is claimed that voters chose these options strategically either to influence the winner's policies or to minimise the scale of the victory of their opposing side, while still preferring the side they voted against to actually win. We refer to this proposed mechanism as mainstream protest voting. We use data from the British Election Study Internet Panel to examine the evidence for such behaviour. In both the EU referendum and 2017 General Election we find no evidence that mainstream protest voting was an important factor in voters' support for either Leave or Corbyn.

Keywords: expressive voting, British politics, expectations, EU referendum, Brexit, British Election Study