White, blue-collar, grey-haired rebels

In the 2010 general election, Ukip gained nearly a million votes — over 3 per cent — three times as many as the Greens, and nearly twice as many as the SNP. Unlike those parties, it won no seats, but its intervention almost certainly cost the Conservatives an overall majority at Westminster. The paradoxical consequence was to hand the balance of power at Westminster to the most pro-European party in British politics, the Liberal Democrats. In the local elections last year, Ukip won 24 per cent of the vote, and is well placed to win the European parliament elections in May. Its impact in next year’s general election is likely to be even greater than in 2010.

So far, explanations of the Ukip phenomenon have been long on assertion but short on evidence. David Cameron notoriously declared in 2006 that the party was composed of ‘fruitcakes, loonies and closet racists’. Around the same time, a Labour cabinet minister told me that Ukip was ‘the BNP in blazers’, while the Observer journalist Nick Cohen believes that Ukip offers ‘a garish picture of what the British right looks like when it has had one beer too many’.

To such critics, Ukip is an illegitimate intruder. Yet, survey evidence has repeatedly shown that a large minority of the electorate, and, in some polls, a majority, want Britain to leave the European Union. In a well-ordered democracy a viewpoint so widely supported should have a voice, not only in the country, but in parliament.

Nigel Farage has struggled to free Ukip from the taint of racism and Islamophobia. Former BNP members are now disqualified from Ukip membership, and Farage has insisted that Ukip will not join Marine Le Pen or Geert Wilders in the European parliament.