Just one final (probably!) dip into the details of last week's YouGov referendum poll. Unlike the recent Ipsos-Mori poll or the second Panelbase poll commissioned by Wings over Scotland, there doesn't seem to have been any direct attempt made to discover how the Don't Knows are more inclined to vote. However, there was one question on the economy which produced responses that correlated extraordinarily closely to actual voting intentions - just 2% of Yes voters thought that an independent Scotland would be economically worse off, while 0% of No voters thought it would be economically better off. So it struck me that the responses of undecided voters to that question might furnish us with a very useful indirect way of detecting which way those people may be leaning. Irritatingly, YouGov haven't provided that particular cross-break, but it's still possible to get a rough idea by extrapolating from the percentages elsewhere in the datasets. These numbers won't be absolutely dead-on accurate, but they'll be reasonably close.
OF PEOPLE WHO DON'T KNOW HOW THEY'LL VOTE IN THE INDEPENDENCE REFERENDUM...
14% think an independent Scotland would be economically better off.
9% think an independent Scotland would be economically worse off.
12% think independence would make no difference to Scotland's economic prospects.
65% don't know how independence would affect Scotland's economic prospects.
(Note : Technically the above numbers include 'won't votes' as well, but they're a relatively small percentage.)
Now I'm not pretending for a moment that these numbers represent some kind of slam-dunk for the Yes campaign. But one thing that is self-evident is that this section of the electorate bears very little resemblance to the No camp's current constituency of support. (For comparison, the figures for No supporters are : Better off - 0%, Worse off - 88%, No difference - 7%, Don't Know - 5%.) So at the very least it would appear that the undecideds are wide open to persuasion by either campaign. And interestingly, it may not be quite enough for the No campaign to fight their opponents to a stalemate on the economic arguments, because the poll also seems to suggest that people who think that independence would make no difference to our economic prospects are at the moment breaking disproportionately for Yes. Again, this is based on an extrapolation, because the relevant raw numbers haven't been provided.
VOTING INTENTIONS OF PEOPLE WHO THINK THAT INDEPENDENCE WOULD MAKE NO DIFFERENCE TO SCOTLAND'S ECONOMIC PROSPECTS:
Should Scotland be an independent country?
So it's just possible that the bar is slightly higher for the No campaign on the economy - to win new converts, they may need to persuade undecided voters that Scotland's economic prospects would actually be worse under independence, rather than merely no better.
Either way, it's worth bearing in mind that if YouGov's headline figures are accurate (admittedly a big if), it wouldn't be sufficient for the Yes campaign to win over a lion's share of the Don't Knows - they would also need a chunk of the No camp's current support. But it wouldn't necessarily have to be that big a chunk.