Opinion polls, as Lord Ashcroft says, offer a snapshot not a prediction. They might not come true in the election itself. They might simply be wrong. They might, they might, they might…

This is what I keep telling myself as I look at the front page of today’s Sunday Times. “Yes vote leads in Scots poll” reads its headline. Underneath, a story (£) explaining that their latest YouGov poll has the Yes campaign leading the No campaign by 51 per cent to 49 per cent. A month ago, No was ahead by 22 points. Now, with less than two weeks until the referendum itself, they are behind by two.

There are more caveats to reach for: the headline figures exclude the roughly 10 per cent of people who class as don’t-knows or won’t-votes; the two-point gap is within the margin of error; there’s a Panelbase poll that has No ahead by four points; and so on. But there’s no denying that the collapse in No’s opinion poll lead is disturbing. At the least, we can now expect the referendum to be a close-run thing.

And so to the question that I asked in the headline to this post: would a close victory be good enough for Better Together? In one sense, of course it would. A close victory would be immeasurably better than a close defeat, for the simple reason that the former spells Union and the latter divide. But it would also clarify just how close we came to Scotland leaving the United Kingdom. How near we were to a terrible, historic milestone.

In that case, I’d expect some of the political fallout to be the same as if Yes had triumphed. Indeed, we get a taster of that this morning. “The general feeling is that the people are just not up to the job on the Labour side,” says one anonymous character to the Sunday Times. There are calls for Ed Miliband to ditch Douglas Alexander as his general election coordinator – because of the horlicks he has made of this.

And what about on the Conservative side? The Sunday Times report also bolsters a story that appeared in the Independent on Friday; that Tory MPs are preparing to oust Cameron should Scotland go it alone. Apparently, two ministers have already let it be known that they would resign. “It’s a golden opportunity for a lot of people who hate Cameron and are just looking for an opportunity to get rid of him,” explains one backbencher. Would that opportunity remain in the case of a narrow victory for No? Perhaps not. But I wouldn’t be surprised if Cameron’s detractors still tried to tar him as the Prime Minister who almost split the Union.

But the worst aspect of a close victory for Better Together would be this: it may not settle the question of Scottish independence for the future. The last YouGov poll for which there are full tables online had the 60-pluses as the only age group in overall favour of the Union. How long before nationalists start referring to the “Independence Generation” below them – and saying they should have another chance to vote Yes?