Could Brexit break the mould of British politics? That is central question facing politicians after the results of the European Parliament election were unveiled on Sunday night, writes Professor John Curtice.
The two parties that are meant to dominate the country’s politics – the Conservatives and Labour – between them secured less than one in four (23 per cent) of all votes cast. This tally has never been anything like this low since the 1920s when Labour displaced the Liberal Party as the principal opposition to the Conservatives.
Of course, in Scotland, their dominance has long been eroded away. That was more than amply confirmed in the Euro-election by the fact that the Conservatives came fourth while Labour trailed in fifth place. But in England and for the most part in Wales, their grip on Commons representation has seemed secure – until now.
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In truth, voters do not behave in European elections in the same way they would in a general election. They tend to be more willing to cast a protest vote against the incumbent vote, to vote for smaller parties, and to support credible Eurosceptic parties. Last week’s ballot provided an environment in which a mass voter defection away from the two largest parties was most likely to occur.
The Conservatives and Labour would not have fared so badly in a general election. Moreover, once a Euro-election is over, any surges of support during the campaign often seem to disappear as rapidly they arose.
But this does not mean we can simply dismiss what happened last Thursday.
For a start, this Euro-election might well not be forgotten as quickly as its predecessors. The issue that seems to have most influenced voters in deciding how to vote – Brexit – is not going to be forgotten very quickly.
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Meanwhile, more than one of the parties that would love to end the Conservative-Labour duopoly performed well. Not only did the Brexit Party come first, but the Liberal Democrats displaced Labour from second place, while the Greens overtook the Conservatives in the battle for fourth place.
This is the first occasion when the duopoly south of the border has faced a two-pronged attack. The Liberal Democrat challenge fizzled out after the party entered into coalition with the Tories in 2010, while only then did Ukip become a serious force.
The initial signs, at least, are that this rather different challenge to the traditional party system might yet prove a more formidable one.
John Curtice is a professor of politics at Strathclyde University and a senior fellow at ScotCen Social Research