IF it’s no broke, dinnae fix it. That must be the SNP election team’s mantra, since their long-running vote-winning strategy appears still to be working after all these years. A survey by pollster Survation suggests – astonishingly – that after 15 years running Scotland, the SNP could make gains in May’s local elections.

All polls come laden with caveats and this one perhaps more than most – it is out of step with past local elections in the level of support it attributes to Independents and Greens, and the SNP’s apparent lead might not materialise, given that similar polls prior to the 2017 locals turned out to be wrong.

Even so, it suggests that once again we go into an election with the SNP comfortably, and perhaps complacently, leading the pack.

Why do they keep winning? Even those who are well-disposed to this government must wonder. This is not an infallible party and, as with any long-running government, the longer they wear out the carpets in the corridors of power, the more apparent their shortcomings become.

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Looking at the recent national picture, the ferry fiasco (five years late and 2.5 times over-budget) and a failure to meet promises on green job creation, have raised serious questions about ministers’ economic competence. Drugs deaths, the loss of Scotland’s status as a world leader on education, the attainment gap and a long-running shortage of nurses and doctors – all of them live issues prior to the pandemic – underline the gap between Scottish Government rhetoric and delivery.

And people get bored. Even Bryan Adams got knocked off the Number One spot after 16 weeks.

Of course there have been successes – the huge increase in renewable energy generation, the Scottish Child Payment and free bus travel for young people (a Green Party policy), to name a few – but we can probably agree the overall SNP record is a bit of a curate’s egg. Yet Ms Sturgeon’s party still looks like coming out on top again.

Political telepathy is a tricky business – what motivates one voter differs from another, and local elections are subject to different influences from national ones – but it seems to boil down to three things: skilful politics on the SNP’s part; the glaring contrast between Ms Sturgeon and Boris Johnson; and a reputation as an OK government.

The SNP’s divide-and-rule strategy – dividing the country down constitutional lines, hoovering up the lion’s share of pro-independence votes, while three sizeable parties split the pro-UK vote and stay in opposition – has been hugely effective. The SNP has stayed in power for a decade and a half without ever commanding a majority of votes.

In short: while the constitutional issue remains in the foreground of voter consciousness, electoral arithmetic will work in the SNP’s favour.

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Nicola Sturgeon also looks good by comparison with Boris Johnson. Thank God we have her, not him, voters said to themselves during the pandemic, assessing Ms Sturgeon to be more serious, hard-working and principled, even if they did not love her.

There is no credible counter-narrative here for the Tories, particularly in light of Partygate – she patently is more serious, hard-working and principled than the Prime Minister (who isn’t, you might ask) – and for a while, her approval ratings surged, reflecting Scots’ collective sigh of relief on that point. Just this week, an exclusive poll for The Herald revealed that two thirds of people in Scotland believe Mr Johnson should resign, unchanged from January when Partygate was at fever pitch, so that contrast is still playing to the SNP’s advantage.

And her government, while rarely eulogised, is seen as good enough. With some notable exceptions, she has espoused broadly popular policies. Her record of delivery is another matter entirely, but the pandemic has given her a temporary reprieve from judgment.

Yet for all the SNP’s superficial popularity, beneath the surface, the tectonic plates could be shifting – because of the cost-of-living crisis. A further poll for this newspaper shows that people are far more concerned about their rising bills than they are about Covid or the NHS. It is a hulking brute of a problem and will affect every household, for months and probably years. According to pollsters BMG, 42 per cent of people say this is the issue that matters most, compared to nine per cent for Covid; that’s drastically different from a year ago, when four per cent said living costs and 40 per cent Covid.

Seventy eight per cent think the Chancellor Rishi Sunak hasn’t done enough to help people through the crisis, unsurprisingly, but the SNP will be concerned that 63 per cent of voters also think Scottish finance secretary Kate Forbes needs to do more too, including two thirds of those who voted SNP in 2019. Voters perceive that neither party has grasped the true enormity of what people are facing.

Council elections are by definition about local issues as well as being a barometer of support for sitting governments.

But the cost-of-living crisis is both local and national, and it’s political TNT. The crucial question is this: could it upset voting patterns that have for years been largely defined by the independence question?

It’s possible. Historically, after all, economic emergencies are what change the shape of national politics – and if that happens this time, then the party to benefit will be Labour.

Labour has come third consistently since 2016, being seen as less trustworthy on the Union than the Tories, but Tory support has dipped because of Downing Street Covid rule-breaking, and apparently gone to Labour, giving Labour a fillip just as the political weather changes. Labour is now set to come second in May.

Anas Sarwar’s party clearly hopes to secure its position by campaigning on the cost-of-living crisis. His manifesto launch yesterday bashed home the message that this would be an election about “one thing and one thing only”, promising hundreds of pounds of support for those struggling with bills. Labour had the SNP and Tories in its sights, with Sarwar urging former Labour voters to “come back home”.

That includes Yes voters – by moving the debate away from the constitution and campaigning on hardship and inequality, Labour could conceivably attract Yes voters in this new, febrile economic climate.

Meanwhile, the SNP faces an ongoing headache of its own making. Ms Sturgeon’s illusory referendum next year has been the tenuous bond holding together her fractious party, but it’s all but impossible to deliver. If and when the plan disintegrates, the party’s unity may do likewise.

So the SNP looks set to do well yet again in these elections. But if Labour does well too, taking back some of the ground it has lost and gaining a new sense of purpose just as SNP unity is threatened, then it could prove to be a meaningful change in Scotland’s atrophied political geography.

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