For the past few years Scottish Nationalist Party members have gathered in Perth for their party conference, easily filling the 2,000 seats in the city’s concert hall. But soon they may have to go elsewhere.

Since the result of the independence referendum was announced in the early hours of September 19th, party membership has tripled to more than 80,000. “The computer servers melted at one point,” says one member, proudly.

Today, party delegates return to Perth. In the afternoon, they will listen to the valedictory leader's address from Alex Salmond. Tomorrow, they will hear the first by his successor, Nicola Sturgeon.

Two months on, the wounds are still visible. Different emotions were evident last evening among shoppers on the city’s pedestrian streets, as the early delegates arrived. For some, the yellow-and-black party symbols provoked smiles and nodding glances that spoke of a shared membership of ‘the 45’ – those who voted Yes.

For others, the emblems caused irritation. Momentum, however, is everything in politics, and it is enjoyed by the SNP. Opinion polls put it at an extraordinary 52 per cent, more than double the figure held by the once-dominant Labour Party.

If reflected in next May’s British general election, the SNP would hold 57 of Scotland’s 59 House of Commons seats, while Labour would have just one, pollster John Curtice has said in an Armageddon-style reading of numbers.

Labour’s fall

Such an outcome, even for the most partisan of SNP loyalists, is unlikely; but the fact that the numbers can even be put into print shows the catastrophic fall that has taken place in Labour’s fortunes in Scotland.

Whatever happens, the SNP will make great gains at the expense of Labour – which badly needs each of the 41 Commons seats it holds, if Ed Miliband is to win power in Westminster next May. The SNP, however, wants a Conservative victory, as it would feed the appetite for a second referendum – which it wants to hold, but it needs to present carefully to middle-ground voters.

“An Ed Miliband government would make it harder for the SNP to make the ‘We’re different’ argument. Labour would be able to do the obvious things: like ending the bedroom tax that would shoot some of the SNP’s foxes,” said one source.

Salmond and Sturgeon's ambitions have been helped by prime minister David Cameron, who linked extra devolution powers for Scotland with greater powers for England just an hour after the Edinburgh result was declared. Cameron's strategy was brilliant politics: extra powers for England means the creation of a two-tier House of Commons, with Labour's Scottish MPs having a reduced voice, or no voice at all on key issues.

In the increasingly fragmented world of British politics, that would deny Labour a future Commons majority, but Cameron’s tactics were dreadful statemanship – fuelling Scots’ ever-present belief that Westminster cannot be trusted.

Salmond has made much play of Cameron’s actions so far, and he will do more, particularly when he returns to the House of Commons next May – which he will, barring something extraordinary happening. Such a high profile for a retired political leader would not be welcomed by most successors, though he and Sturgeon have become more of a joint ticket over the last year or so.

Less relevant

The SNP in the past has always been less relevant as House of Commons elections loom. Scots have been happy to vote for them at Holyrood but preferred Labour when it came to a straight fight against the Conservatives.

Now, however, Sturgeon has laid out the possibility that dozens of SNP MPs, if elected, could offer conditional support to a Labour government in Westminster on a case-by-case basis.

This has nothing to do with wanting to see Miliband as prime minister. Instead, it tells disgruntled Scottish voters that they no longer have to give ‘one more chance’ to Labour.

Scottish Labour is electing a new leader following the decision of Johann Lamont to step down after she lambasted the party's London leadership for seeking to control everything.

Former cabinet minister, Jim Murphy – the most visible Labour face during the referendum – is attracting most coverage, though MSP Neil Findley has the support of most trades unions.

The leadership race was necessary, but the timing unfortunate, since it leaves Scottish Labour rudderless as the Smith Commission finalises its draft devolution plans. The commission – part of 'the vow' made by Cameron, Miliband and Liberal Democrats' Nick Clegg before the vote when they feared defeat – is operating on a tight timetable.

Extra powers

Heads of agreement about the extra powers that should be given to Holyrood are to be concluded by November 30th, with a draft Bill ready to go before MPs by the end of January.

Extra powers are coming. However, it is not clear if they will match the last-minute promise that they will be substantial, partly because no-one can agree on what ‘substantial’ means.

The Conservatives are ready to accept that Holyrood should have direct control over income tax rates and bands, along with powers over many welfare entitlements.

Labour’s official policy does not go that far. Miliband fears that such a change would mean Scottish Labour MPs in the Commons would be excluded from votes on such matters there. Murphy says he can stand up to London, but he is despised as a Blairite by many in Labour: “And calling somebody a Blairite up here is as bad as calling somebody a Tory,” says one source.

Findley has been relatively unimpressive in the Holyrood chamber, but is far more ambitious about devolution, and touching the parts in the Labour organisation that Murphy cannot reach.

“Murphy is the one that people will vote against. Yes, he would do better on First Minister’s Questions against Sturgeon than Findley would, but he is not in Holyrood. And he can’t be, in the short-term,” said one Labour figure.

Equally, however, Murphy is the one most likely to reach beyond the Labour heartland – which it will need to do to gain power in the 2016 Holyrood election. However, it is the heartland that is needed to stave off disaster.