It is difficult to overstate the importance of Glasgow to the Labour Party. Since the (arguably mythical) days of 'Red Clydeside', the city has almost formed part of the Labour movement’s central nervous system. Scottish Labour’s HQ is in Scotland’s largest city, while for decades majorities – in local authority, Scottish Parliament and Westminster elections – have been taken for granted.

At least, that is, until recently. From a Labour vantage point, the barbarians (ie, the SNP) started scratching at the city’s gates in 2008 when Glasgow East fell to the nationalists’ John Mason in a Westminster by-election. Although Labour secured all of the city’s MPs at the 2010 general election, in elections to the Scottish Parliament the following year Glasgow’s Labour MSPs fell like flies.

For the SNP, which had always struggled to win urban support, it was an important psychological victory. If the party could take Glasgow from the 'auld enemy' (Labour), then anything was possible. Almost immediately the SNP set its sights on snatching Glasgow City Council from Labour in this May’s local authority elections. If successful, it would signal that the onward march of nationalism was continuing apace.

Labour is, therefore, equally determined to hold on to its historic heartland. “There have been resources and people coming in from across Scotland to help with the party’s campaign in Glasgow,” says a Labour strategist, “and clearly the only thing on the UK party’s radar in all of this is Glasgow. It’s totemic. Everyone knows that.” Writing last year, Labour’s Glasgow election agent, Dominic Dowling, warned that unless the party got its message across, the outcome “could be devastating”.

The SNP, meanwhile, has been pulling out all the stops with a typically slick and well-funded campaign. Nicola Sturgeon, deputy first minister and a Glasgow MSP, has regularly depicted Glasgow as a local authority in meltdown. “We face here a Labour Party that is crumbling before our eyes,” she said in one speech, “a Labour Party that is discredited, that is losing councillors hand over fist.”

In this, there is more than an element of truth. Not only did Steven Purcell, leader of Glasgow City Council between 2005–10, resign amid allegations of drug addiction and corruption (the Crown Office recently stated there was “insufficient evidence” of criminality), but his successor, Gordon Matheson, presided over the de-selection of almost a third of his councillors, while in February his budget scraped through following a nail-biting council meeting.

Even so, this is a difficult election to read. Media coverage in Scotland has been relatively low-key – the looming independence referendum casts a long shadow – while there has been no dedicated polling. These are also the first local government elections in Scotland since 2007, and also the first since 1995 to have been 'de-coupled' from a national election (held concurrently with elections to the Scottish Parliament).

Thus, turnout will probably be, in the words of one observer, “wickedly low”, while in cities like Glasgow, it is almost impossible to gauge whether the result will be decided by local or national issues. The SNP has been hoping for the latter, essentially re-running its successful 2011 Holyrood campaign and emphasising team, record and vision, as well as reminding voters of a long-running council tax freeze.

Not everything, however, has played in the SNP’s favour. Allison Hunter, the party’s group leader on Glasgow City Council, has had a gaffe-prone campaign, admitting that victory in Glasgow could be considered “a stepping stone to independence”, while – pressed to name policies she would implement as leader – said she had not “thought about that yet. Actually, I’m not an out-there leader. I’m a team leader. So we haven’t actually thought about that yet.”

Nevertheless, Labour is nervous. Almost no-one is predicting that Matheson will manage an outright majority (he currently heads up a minority administration), while the SNP, already Scotland’s largest party in local government, continues to ride high in the polls. That said, Scottish councils are elected by single transferable vote, which produces the intimidating prospect – for both Labour and the SNP – of becoming victims of their own success.

Conspicuous by his absence from the campaign in Scotland has been a certain Ed Miliband. Labour strategists claim this is because “he wants to let people get on with their own thing”, but it could also be through fear of becoming associated with further electoral failure. David Cameron regularly taunts him about his New Year message prior to last May’s Holyrood election – “the fightback begins in Scotland” – and, particularly in the wake of the Bradford West by-election, Miliband perhaps recognises his limited appeal north of the border.

Would the loss of Glasgow be another nail in his leadership coffin? Some London commentators certainly think so, although it would be difficult to pin defeat on his campaigning visits, as in 2011 (when every Labour seat Miliband visited fell to the SNP). So, what would victory look like for his party in Glasgow? “Frankly,” says a Labour source, “anything other than an SNP administration. There would have to be a Labour-led administration of some hue.” Even the most optimistic SNP strategists do not expect to gain overall control.

Others urge caution, pointing out that if commentators and pollsters have learned anything from the experience of 2010-11, it is that the Scottish electorate is relatively sophisticated, and therefore perfectly capable of backing a different party at each layer of government. Independence might dominate the agenda in the Holyrood and Westminster bubbles, but on the ground in Glasgow litter, crime, drug abuse and urban decay could be more pertinent factors.

As one columnist recently put it, for Labour to lose control of Glasgow City Chambers would be “akin to waking up one morning and finding that Ian Paisley has taken control of the Vatican”. For the SNP, meanwhile, victory would be the perfect springboard for launching its formal 'Yes' to independence campaign, conveniently planned to get underway within weeks of May’s potentially game-changing local authority elections.

Tags: Alex Salmond, David Cameron, Ed Miliband, Glasgow City Council, Labour Party, Scottish independence referendum, Scottish National Party