Inside Westminster: The Scottish referendum is a judgement of both the head and heart

Many of the undecided want to vote for independence, but their heads aren't convinced

When David Cameron visited Edinburgh last month, he was greeted by anti-cuts protestors dressed as pandas, to remind him that there are more giant pandas in Scotland (two) than Conservative MPs (one).

The Prime Minister accepts he is not the right man to front the campaign against independence before the referendum in September. The Liberal Democrats have a proud tradition in Scotland, but the referendum comes at the worst time for them to take the lead. Many Scots will not forgive them for hopping into bed with the hated Tories at Westminster.

So that leaves Labour, which has 40 of Scotland’s 59 MPs. But it has not recovered from the seismic shock of the Scottish National Party’s outright victory in the 2011 Scottish Parliament elections, under a system Labour designed to prevent any party winning an overall majority.

Until this week, Labour's impact in the independence battle has been diluted by personal rivalries and the traditional tension between Scottish Labour and the party’s national leadership. Until his intervention on pensions, Gordon Brown, who still commands respect in his homeland, had largely done his own thing, avoiding the Better Together campaign led by his auld enemy Alistair Darling. Even those involved in it tell me privately that this cross-party campaign is too unwieldy and slow to react to events because everything has to be signed off by everyone. Crucially, “the Westminster parties”, as Mr Salmond dismisses them, promise more devolution if Scots reject independence but cannot agree on what further powers would be devolved. This means their offer of further devolution is fuzzy and even less likely to be believed by sceptical Scots.

Most Scots would favour the “best of both worlds” option of more freedom combined with the security of the Union. But “devo max” is not on the ballot paper and in five months they must decide whether to vote Yes or No to full independence. It is a judgement of both the head and heart. Those who have firmly made up their minds have decided on both counts. The huge number of undecideds – perhaps 30 per cent--make the result too close to call. The No camp’s lead has narrowed, with some polls putting it only three to five points ahead (when “don’t knows” are excluded).

In their hearts, many of the undecideds want to vote for independence. But their heads are not yet sure. This is where the battle is now being fought.

The London-centric view is that Better Together needs to be more “positive” about the Union, rather than try to scare Scots by warning them they could not keep the pound if they vote Yes. George Osborne's nuclear weapon boomeranged, as Scots tended to believe Mr Salmond’s argument that the Government would negotiate a currency union with Scotland if the crunch came as that would be in the national interest. Better Together will return to the sterling issue and try to get its message right.

In Scotland, No campaigners believe the heads of the undecideds will not be persuaded by emotional talk about the wonderful state of the Union. They insist the debate must be framed in transactional terms, to explain how people would benefit personally from remaining in the UK. Polls suggest that Scots would vote heavily against independence if it would leave them £500 a year worse off but Yes by a clear margin if it would make them £500 better off.

So Ed Miliband, who took his Shadow Cabinet to Glasgow yesterday, was on the right territory as he promised that a Labour Government would ban exploitative zero hours contracts – a win for the estimated 90,000 Scots on them and a powerful message that social justice can be best ensured at UK level.

Mr Miliband may have located Mr Salmond’s Achilles heel. The SNP is love-bombing present and former Labour voters, who probably hold the key to the result. Mr Salmond promises social justice too but his record is open to question. As in England, wealth has been redistributed upwards, not downwards. What is progressive about his plan for a 3p cut in corporation tax; no 50p top rate of income tax; and the Scottish Government’s universal provision of free prescriptions, a council tax freeze benefiting the wealthy most and free personal care for those who could afford to pay? How sustainable would these policies be if Scotland goes it alone?

Mr Miliband would have a better chance of wooing left-leaning undecideds if he looked set to form the next Government but again the polls are too close for comfort. And yet he is well-qualified to lead the charge north of the border. Many Labour supporters were alienated by New Labour. Having positioned himself as “not Blair”, Mr Miliband ought to be able to reap a dividend in Scotland.

If Labour can continue to make the weather as it did this week, then I suspect the No camp will just manage to keep Mr Salmond at bay in September. But it may be a pyrrhic victory.

At the start of the campaign last year, Better Together hoped to win comfortably in order to settle the independence question for a generation. The feeling in both the Yes and No camps now is that this is not going to happen. So a No vote would be followed by more devolution and, sooner rather than later, another referendum. Scotland is travelling on a one-way street. And all the road signs suggest that full independence is a matter of when, not if.

CAMERON, MILIBAND AND CLEGG: WHO'S GETTING THE RED CARD FIRST?

The sacking of David Moyes sparked much gossip in the Westminster village about the parallels between politicians and football managers.

David Cameron, Ed Miliband and Nick Clegg know that at least one of them is almost certain to be out of a job after next year’s general election. They are in denial in public while, behind their backs, their “colleagues” speculate furiously about who would take over.

Mr Clegg has to say he will lead the Liberal Democrats until 2020, after a silly but inevitable media frenzy at his party’s spring conference. An aide said he would stay on if the Lib Dems were still in government after the election. The implication was the truth: Mr Clegg will stand down before the following election if either Labour or the Conservatives win a majority.

If Labour is not in government, Mr Miliband’s party would surely show him the red card. Some Tory MPs claim they would oust Mr Cameron unless he wins an overall majority.

If you put them on a lie detector machine, I reckon that Labour and Tory MPs would name Mr Clegg as the most likely survivor because most expect another hung parliament. But the election is going to be so close that nobody knows whether it will be Mr Cameron or Mr Miliband who suffers the Moyes treatment.