IF a week is a long time in politics, the past month has been a political eternity. If you’re an SNP politician, particularly if you’re Humza Yousaf, that eternity must feel like a never-ending nightmare.

From resignations over lies about the party’s membership to the arrest of Peter Murrell and police raids on both the party’s Edinburgh headquarters and Nicola Sturgeon’s home, the new First Minister couldn’t have had a worse start to his leadership.

The flip side of this political carnage is Scottish Labour’s quiet rise in the polls. Anas Sarwar’s party has come within five or six points of the SNP in some recent polls – a level of support at which they could realistically become Scotland’s largest party at Westminster.

The Rutherglen and Hamilton West by-election, assuming a recall petition gathers enough signatures to unseat Margaret Ferrier, would come at an ideal moment for them.

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Most election models predict that Labour would win the seat in a general election. Consider that the Greens and Alba may run, that SNP voters may protest vote against the party, or abstain from voting, and that Ferrier’s misconduct will play a large role in local campaigning, and this by-election is Labour’s to lose.

Winning would solidify a sense of momentum going into 2024, and a significant general election comeback would further boost the party ahead of their first real shot at breaking the SNP’s grip on Holyrood since 2011.

So, it is no surprise that Labour’s supporters are bullish about their electoral future. They may even feel that they can sit back and allow the SNP’s slow-motion implosion to do the work for them – after all, oppositions don’t win elections, governments lose them.

But this would be a fatal error.

Labour will face significant obstacles on the road to power in Scotland, rooted in the same political dynamics that have underpinned Scottish politics since 2014 and have seen the party repeatedly go down to heavy defeats.

The Herald: Humza YousafHumza Yousaf (Image: free)

Firstly, the constitutional question shows no signs of going away. According to Savanta UK’s polling since October, the number of Scots who think that independence is one of the country’s top issues is unchanged.

And while the number of Scots who say they would vote SNP if an election were held today has fallen, from 46% to 39% at the end of March, support for independence remains unchanged at 45%.

The SNP’s decline since October has been driven by former SNP voters abandoning the party, with one-in-four 2019 SNP voters no longer saying they would vote for the party. Most of those say they would now vote Labour – in October, 8% of 2019 SNP voters said they would now vote Labour, and that figure has since risen to 17%.

So, Labour’s support in the polls increasingly includes a growing number of pro-independence voters. At the same time, around one-in-five 2019 Conservative voters would also now vote Labour.

Between them, they account for a third of the 33% of Scots that would vote Labour in a general election. Without them, Labour would achieve around 23% of the vote and could well come third.

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The challenge is clear – Labour must find a way to maintain a voter coalition that spans the constitutional divide, regardless of how salient the constitutional question is. Lean too heavily towards one flank or the other, in rhetoric or policy, and they risk alienating the opposite flank.

Gordon Brown’s proposals for constitutional reform represent one approach to this. The challenge for Anas Sarwar is converting the proposals adopted by Keir Starmer into a digestible set of pledges that appeal to independence supporters but don’t open the party up to allegations of appeasement from unionists.

Assuming he does, and Labour are in government following a 2024 general election, he will then need to show some progress in fulfilling those pledges by the 2026 Holyrood election. But it is highly likely that, for example, abolishing the House of Lords in favour of an Assembly of the Nations and Regions will be an arduous and years-long project that will not have borne fruit by 2026.

That prospective Labour government has been positioned by many as a potential advantage for Labour going into a Holyrood election. The SNP line that independence is necessary to escape Conservative governments, for example, would become less effective.

But it also comes with dangers. Westminster is a deeply distrusted set of institutions in Scotland, particularly among those pro-independence voters Labour needs to win, and the emergence of that distrust pre-dates the recent Conservative governments.

Labour being in government would allow the SNP to paint Labour as the Westminster establishment, and position themselves as the opposition in an election in which they are, by any definition, the incumbents.

It may also open up opportunities to paint Scottish Labour as incapable of standing up for Scotland’s interests – something that pro-independence voters will require as table stakes before switching their votes, and the SNP continues to enjoy large polling leads over Labour on.

There is a great deal of truth in the notion that it is governments that lose elections, but oppositions still need to do enough to win them.

A favourable political environment and growing momentum cannot be confused with an inexorable rise to power. Labour has crucial strategic questions to answer before the next Holyrood election if they hope to put Anas Sarwar in Bute House.

How will they build and balance a voter coalition spanning the most polarising issue in Scottish politics? How will they avoid being painted as the Westminster establishment that Scottish voters instinctively distrust? How will they prove that they can stand up for Scotland’s interests?

There’s a long road to the 2026 Holyrood election, one that will undoubtedly take many twists and turns. The dynamics of Scottish politics will place substantial demands on Anas Sarwar and his party, and they must meet those demands if they hope to replace the SNP as Scotland’s governing party – they can’t sit back and hope the SNP does all the work for them.