THIS time last year, Alistair Darling was in the fight of his life leading the cross-party campaign for a No vote in the independence referendum.

He won, by a decisive 10 percentage point margin, when the votes of 3.6 million Scots were finally counted in the early hours of September 19.

Since then, life has been quieter.

He stepped down from the Commons prior to the General Election in May and since then has enjoyed a foreign holiday with his wife Maggie, a former Herald journalist, and found time to tend the roses in the garden of his Edinburgh home.

But it cannot have felt like a spell spent relaxing on his laurels.

That 55 per cent to 45 per cent victory was narrower than most observers predicted when the campaign kicked off in 2012.

The result propelled the SNP to a landslide election victory in Scotland, mainly at the expense of his own party, Labour.

And with some recent polls showing a majority in favour of independence, the big question in Scottish politics a year on from the referendum is if and when a second one might take place.

Mr Darling does not believe most Scots are in a rush to repeat a process which, he says, aired the arguments but left a legacy of division.

Even Nicola Sturgeon, he insists, does not want an early re-run.

"I think she does not want to have a referendum any time soon but she cannot tell her supporters to go home and think about other things for a few years.

"The political reality for the Nationalists is they have to keep a lot of people on board.

"They have to hold out the hope of a referendum," he says, adding that as well as appeasing die-hard Nationalists, talk of another referendum shifts the debate away from the SNP's faltering record on education, health and policing.

In her manifesto for next May's Holyrood election, Ms Sturgeon will effectively reserve the right to call a referendum at any time she believes the SNP could win.

Mr Darling is not holding his breath.

Despite the surge in support for the SNP, the economic case for independence, which failed to sway a majority of Scots, is weaker now than it was, he says.

He cites figures showing the collapse in oil prices since last year has blown a £10billion hole in Scotland's public finances.

"There has been a huge structural change in the Scottish economy," he says.

"There is oil there, but no-one is expecting the oil price to go back up to anything like what it was 12 months ago.

"We were told we were scaremongering 12 months ago when we said oil could dip below $113 per barrel. It's less than half that now."

He adds: "The economic case, which was always difficult, is much more difficult to make."

The former Chancellor, who steered the UK through the 2008 banking crash and the recession that followed, argued the level of economic growth required to plug the gap in Scotland's finances was unachievable.

An independent Scotland would face tax rises or spending cuts "that would make George Osborne's austerity look like a Sunday afternoon picnic".

As for the possible currency of an independent Scotland, an issue that dogged the Yes campaign, it remained a "real problem," he says.

Asked if a second referendum might happen at some point, he says: "I honestly don't know."

He is clear, however, the UK Government should not attempt to block a second vote.

Mr Darling also dismisses criticism of Better Together, the often uneasy No alliance between Labour, the Conservatives and the Lib Dems, which he led with Stoic determination.

Willie Rennie, the Scottish Lib Dem leader, described the campaign as "secretive" and "shambolic," while a new book, Project Fear, by journalist Joe Pike, paints a picture of chaos, confusion and organisational blunders by those charged with saving the Union.

"There are things any campaign could do better. We won by 10 percentage points, that's what people should remember," says Mr Darling.

He argues strongly, however, it is now the job of the those parties in favour of Scotland staying in the UK to make the case for it.

"That's what political parties are for," he says.

It is clear he would rather discuss the package of tax and welfare powers being devolved to Holyrood by the new Scotland Bill than hark back to the referendum.

He sees further devolution, which follows last year's Smith Agreement, as an exciting and positive development.

But he wants the "fiscal framework," the financial deal that will underpin the package by resetting Scotland's budget and borrowing powers, to be opened up to the public.

If not, he fears the SNP will attempt to capitalise by claiming Holyrood is getting a raw deal.

Even after a restorative six months away from frontline politics, it seems Scotland's constitutional future still haunts him.