Winner in 2019 of predecessor seat of Coatbridge, Chryston and Bellshill: Steven Bonnar (SNP)

AS the 2015 General Election approached, a Labour blogger down south tried to wake up his party colleagues in England to the scale of the electoral tsunami that was about to hit in Scotland.

On the opinion poll projections, he pointed out, Labour would lose even Coatbridge to the SNP. “Coatbridge!” he repeated with synthetic incredulity, as if he lived in a world where the name Coatbridge would provoke instant recognition from his readers as the classic example of the safest of safe Labour towns in Scotland, or where they would already know off by heart the demographic factors that had made it so secure.

If there is indeed something that marks out Coatbridge as different from other former Labour heartlands, it’s surely religion and ethnic origin. It has one of the highest densities of Roman Catholics in Scotland, and thus much of the population has relatively recent Irish ancestry.

An Irish background has traditionally correlated in Scotland with poverty, poor health outcomes, and loyalty to the Labour Party.

So it’s quite true that Coatbridge and Bellshill’s predecessor constituencies had been rock-solid for Labour from the mid-1930s onwards – with the intriguing exception of 1959, when a Tory candidate came within less than a 2% margin of capturing the old Coatbridge and Airdrie seat.

That was the election in which Tory Prime Minister Harold Macmillan boasted “you’ve never had it so good!”, but that’s unlikely to have been a sentiment that chimed with many people in Coatbridge. Instead, there may have been a soft sectarian aspect to the Tory surge, with Protestant voters reacting against the Labour loyalties of their Catholic neighbours.

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But that wasn’t the start of something big for local Tories. Harold Wilson’s two election victories in the 1960s helped re-establish Labour dominance in the constituency, and since then no Tory candidate has got within 10,000 votes of winning any seat containing Coatbridge.

The Tories were consistently replaced by the SNP as the second most popular party from 1992 onwards, but the SNP were just as much also-rans to Labour as the Tories had been before them.

Going into the landmark 2015 General Election, the SNP required a seemingly impossible 25% swing to capture the Coatbridge, Chryston and Bellshill seat, bigger than the target they faced in almost all other Labour-held constituencies.

The southern Labour blogger had probably anticipated a fairly even swing across Scotland that might have seen the SNP just barely get over the line.

But that wasn’t how 2015 turned out at all. Where the Labour majorities had previously been biggest, the swings to the SNP were even more gigantic. The SNP’s Phil Boswell ended up humbling Labour by an astounding margin of more than 11,000 votes in Coatbridge, Chryston and Bellshill.

It appeared that the ties that had bound Labour to Catholic communities had been broken as fundamentally as the ties that bound the party to any other demographic. There was no apparent reason to think that Coatbridge would be more vulnerable to a subsequent Labour comeback than anywhere else in the central belt.

But in a further twist, that assumption proved wrong too.

The constituency was one of a handful in Scotland that were unexpectedly won back by Labour under Jeremy Corbyn (above) in 2017, and again, the swing was much higher than the national average.

It seemed the local conversion to the SNP had been shallower than hoped and that in any election in which Labour performed tolerably well across Scotland, voters in Coatbridge would return to their old party as easily as they might slip on an old coat.

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Although Steven Bonnar reclaimed the seat for the SNP in 2019, his winning margin of 11.6 points means that on a uniform swing and taking into account boundary changes, Labour will gain it back this year even if they are as much as 15 points behind the SNP.

This will be one of toughest constituencies for the SNP to defend anywhere in Scotland, and an immense local campaigning effort will be required to defy the odds.