WE may have to wait for the memoirs to know for sure whether the SNP leadership cracked open the champagne after Jeremy Corbyn’s landslide victory on Saturday or reacted with deep apprehension. But it seems logical that they would have been happier with a routine win for Andy Burnham that was firmly on the cards until Corbyn sneaked onto the ballot paper with minutes to spare. That’s not to say there is no chance that Corbyn won’t ultimately prove more helpful for the SNP’s electoral prospects than Burnham might have done, but he injects a dose of unpredictability into the forthcoming Holyrood race that simply wouldn’t have been there under a Continuity Miliband leader. Nicola Sturgeon had no choice in the matter, but she would surely have preferred not to change a winning formula.

It’s true that polling in recent weeks has offered some reassurance to the SNP on the potential impact of Corbyn. In late August, Ipsos-Mori found that 34 per cent of Scottish voters were less likely to vote Labour if Corbyn won, compared with just 23 per cent who were more likely to do so. The snag is, though, that people are generally not very good at answering hypothetical questions about what will affect their voting choices in the future. It’s only now that we’re faced with the astonishing reality of the most left-wing Labour leader since 1935 that we’ll start to discover the electorate’s true attitudes.

That said, Corbyn will not be a candidate for First Minister in May. One of the main lessons of the 2011 Holyrood election is that UK-wide factors are likely to fade into the background in the run-up to polling day, as voters focus on the real choice between Sturgeon and Kezia Dugdale. At best, the Corbyn factor might help Dugdale to become a more attractive leader in the eyes of traditional Labour voters, by freeing her up to chart a more left-wing course, and perhaps slaughter a sacred cow in the shape of Trident.

The downside for her will be the Labour civil war that is bound to rumble on over the coming months. The charge that Scottish Labour are ‘Red Tories’ may no longer have any validity, but the alternative jibes of ‘utter shambles’ and ‘unelectable at UK level’ could prove just as potent. For that reason, in spite of the fact that we are venturing into totally uncharted territory, the smart money remains on a second overall SNP majority next year.

James Kelly writes the blog Scot Goes Pop