The polls in Scotland just before the last election showed a 21-point lead for SNP over Labour. The SNP went on to take all but one of Labour’s 41 Scottish seats. This week Theresa May called a general election in the wake of polls showing her Conservative party 21 points ahead of Labour. Could Labour now be headed for a Britain wide meltdown of the kind that they suffered in Scotland two years ago? Intriguingly, the distribution of the 2015 Labour share of the vote across the seats they are defending now is very similar to the distribution of their …

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