The British Government agreed to let Alex Salmond have a referendum on Scottish independence for one simple reason: because it was confident of victory. Indeed, not only did it expect to secure a No vote, but it hoped for a large one – thereby destroying the “threat” of Scottish nationalism for a generation or more.
But with less than five months to go to polling, such confidence now looks misplaced. Whereas for most of last year the polls pointed on average to No winning by a margin of at least three to two, this year the margin has narrowed considerably.
Since George Osborne announced in mid-February that an independent Scotland would not be allowed to share the pound with the rest of the UK – a claim that, far from frightening Scots, was greeted with widespread disbelief – the No tally (once “don’t knows” are left aside) has slipped to 56 per cent, with Yes on 44 per cent.
Every single polling company now puts the Yes vote higher than it did before Christmas. If the Yes side maintains its recent rate of progress through to September the outcome could well be a photo finish.
Yet in truth there is considerable uncertainty about exactly how close the race is. This is because the polls do not agree with each other. Three companies – ICM, Survation and (especially) Panelbase – are consistently producing higher estimates of the Yes vote than TNS BMRB, YouGov and (especially) Ipsos Mori.
If the former group of companies is correct then the race is already very tight indeed, with a Yes vote of between 45 per cent and 48 per cent. If the latter are right then although the race might be closer than it was, the Yes tally is still at no more than 42 per cent and may be even less.
Moreover, some of the most recent increases in the average level of Yes support have arisen because Panelbase has been polling particularly frequently in recent weeks – thanks to commissions from a variety of pro-independence organisations who appear to have decided that the company is their favourite pollster.
In fact, five of the six polls published so far this month have suggested the progress of the Yes campaign has stalled, and that it needs another push if it is to have a chance of winning. Even so, that could still mean that Scotland is set to have an unusually hot and sticky political summer.
John Curtice is a professor of politics at Strathclyde University and runs a blog on polling in the referendum at: whatscotlandthinks.org