He runs, arms outstretched like a boy playing aeroplane. Paul Cruikshank's party has just lost Glasgow but the 24-year-old is doing a victory lap around the city's Emirates Arena. "Thirty-seven seconds," says his friend Eva Murray, a councillor, as she clocked the Labour activist over what, when the counting tables are folded away, reverts to a 200m indoor track.

His chest heaving and his brow shining, Paul throws back a bottle of water. "I said I would run round the hall if Hugh Gaffney won Coatbridge," he explains, "and he did." A Labour member since he was 16, Paul has experienced eight years of steady decline for his party in Glasgow, in Scotland and in the UK. Until now; now he gets to run off the sheer excitement of what felt like a comeback.

Because Labour, Corbyn Labour, was on a high even as they regained just one of the Yes City's seven Westminster seats. "It's Six-One," said one Glasgow veteran. "That might not sound like a good football score but we are back in the game." Just a few weeks ago, after losing the city council, their decades-old stronghold, to the SNP, they did not expect to be.

So even as they lost, they celebrated. "Any Labour person who would have told you this is what they expected would have been lying," declared Anas Sarwar, who was dumped as an MP in the last general election in 2015 before finding a place under the list system in Holyrood. "We had hoped to make progress but we have done much more. This result in Glasgow shows Labour is back fighting for progressive values that people of Glasgow believe in."

Mr Sarwar is no Corbynista. Nor is Frank McAveety, the recently ousted leader of Glasgow council. But both men found themselves bigging up Labour's new-found radicalism as they fussed over their new prize politician, Paul Sweeney, like doting aunts.

Less than a year Mr Sweeney - along with more than 300 Labour figures, including prominent Glasgow ones - was calling for Mr Corbyn to go. In the early hours of Friday morning, his tone was quite different as he repeated his leader's mantra of "for the many, not the few" after being named the new MP for Glasgow North-East, once Labour's safest seat in Scotland.

Mr Sweeney was a surprised as anyone else to win. Moments before officials whispered his result - sparking a victory celebration greater and louder than anything the SNP could muster - he had been fretting about the size of bundles of ballot papers. Was he really just a bit ahead? How tight were the elastic bands around the votes? His majority over former MP and MSP Anne McLaughlin of the SNP? In the end it was just 242.

The returning officer had still to announce Mr Sweeney's win when the BBC thrust a camera in to his face. His cheeks flushed, he spat a gum he had been frantically chewing in to his hand and composed himself for live TV. Mr McAveety, an old hand from when Labour could be sure to win, made a rectangle with his fingers as he looked on: "He's my MP.". A place in parliament may have come earlier than Mr Sweeney expected. But his party felt reason to be confident that they have found a credible voice in a the shipbuilding engineer.

And yet, on the sidelines of the count, amid all their celebrations, there were notes of caution from Labour and even hints at collaboration with their nationalist arch-enemies. In Edinburgh, their Scottish leader attributed her party's relative revival to her tough stance on a second independence referendum. In Glasgow, some Labour sources thought Corbyn had helped them to hoover back up some Yesser votes they had lost in 2015 as well as diehard unionists who would put the cross next to whoever they thought would put a stop to the SNP.

That presents a problem. It can be hard to please both those Glaswegians, "Yes but Corbyns" and the "Anybody but Sturgeons". But gulf between the Labour left and SNP may not - constitutional niggles aside - be so big. Many Glasgow voters just do not share the tribalistic rivalry of some partisans. They can switch between the two parties. Glasgow East, for example, flipped from Labour to SNP in 2008, back to Labour in 2010, then SNP in 2015. The Nationalists held on in 2017, but with a majority of 75 for their only new member, David Linden.

Just how much Corbyn Labour and the SNP have in common was summed up by the closest contest in Glasgow. In the city's South-West, SNP incumbent Chris Stephens defeated fellow trade unionist Matt Kerr of Labour by 60 votes in what one source described as "the battle of the bonnets". Mr Stephens picked out Mr Kerr for praise in his acceptance speech, saying he agreed with his counterpart on almost everything. Challenged about this meant for future relations between the two parties, Mr Stephens, glowing with joyous relief, answered simply: "We're comrades."