Media coverage of support for independence in opinion polls often seems to be a case of 'heads I win, tails you lose', and you'd have to say that Jeremy Corbyn suffers the same problem at the hands of a hostile press at UK-wide level. When the Tories have a big lead it's portrayed as a catastrophe for Corbyn, but when the race is closer to being even-stevens he doesn't get any credit for it - the story swiftly changes to "the opposition party should have a big lead at a time when the Tories are in such disarray". Well, for what's it's worth, we're hearing the latter narrative at the moment, because after the Tories opened up what looked like a potentially decisive lead in the aftermath of the Independence Group breakaway, they've now been pegged back. Take, for example, the latest Opinium poll...
Britain-wide voting intentions (Opinium):
Conservatives 36% (-2)
Labour 35% (+1)
UKIP 9% (+1)
Liberal Democrats 7% (-1)
SNP 5% (n/c)
Greens 4% (+1)
Plaid Cymru 1% (n/c)
Scottish subsample: SNP 46%, Conservatives 26%, Labour 17%, UKIP 6%, Liberal Democrats 4%, Greens 1%
It's not that Labour have really recovered from their post-breakaway slump, it's more that disgusted Brexiteer voters have turned away from the Tories (at least for the time being) and towards UKIP. I suppose some would argue that once an election campaign is underway, the Tories would be able to squeeze the UKIP vote, but that's not necessarily a silver bullet, because there's a significant Green vote there for Labour to squeeze as well.
I said recently that the fallout from the Independent Group breakaway had left the SNP almost assured of victory in Scotland at the next Westminster election. That's probably still correct, because Scottish Labour have too much of a deficit to realistically make up. Nevertheless, if Labour start the election campaign within striking distance of the Tories at UK level, there would be more cause for concern for the SNP, because any momentum for Corbyn in England could bring Labour back into the game in Scotland. We all remember what happened in 2017 - the swing from SNP to Tory was not a massive surprise and was factored into our expectations, but the real problem was the late swing from SNP to Labour, which nobody had really seen coming and was purely caused by momentum generated south of the border.
One thing that became clear in 2017 is that the post-election media narrative is driven mainly by the expectations game and by direction of travel. You had otherwise sensible commentators portraying a landslide SNP victory as a "disaster for Sturgeon" simply because the SNP had lost seats and underperformed expectations. That provides an opportunity this time around, though, because 39 or 40 seats would have to be reported as a good result, even though exactly the same outcome would have been considered a setback two years ago. I think it's particularly important that the direction of travel is not just seen to be towards the SNP but also against the Scottish Tories, ie. the SNP need at least a small net gain of seats from the Tories and not just from Labour. At a minimum that would mean regaining Stirling and holding onto Perth & North Perthshire.
I don't think these are questions for the distant future either - I'm coming round to the idea that there is a greater than even chance of an election this year. Stephen Bush said yesterday that the Prime Minister's implied threat of an election to avoid a soft Brexit doesn't make sense because there isn't enough time to hold an election before the 12th April cliff-edge. But what we know about Theresa May is that she wants her legacy to be the delivery of Brexit, and she won't regard continued customs union and/or single market membership as being a 'real' Brexit. If an impractical option like an immediate general election is the only way of salvaging that legacy, I could imagine her doing it. Another possibility is that the deal will pass, and that whoever is Prime Minister for the next phase of negotiations will feel that an election is unavoidable if we don't want deadlock further down the road.