Do the SNP have a genuine chance of beating Alistair Carmichael in Orkney & Shetland?

As you may have heard, Danus Skene was unveiled as the SNP's candidate for Orkney & Shetland a few hours ago.  He's 70 years old, which in combination with 20-year-old Mhairi Black's candidacy in Renfrewshire is a really encouraging sign that the party aren't interested in putting forward a slate of safe, dull, identikit candidates in an attempt to press home their current opinion poll lead.  Instead, the person considered to be the best option available for each constituency is getting the nod, regardless of age, gender, etc.  When Mhairi Black first started making headlines, our old friend Mike Smithson derisively snorted that any party putting forward such a young candidate was showing a complete lack of respect for the electorate.  He apparently didn't possess the self-awareness to spot the extraordinary disrespect he was showing to all young people with that remark.

It's true that I've said many times before that the current cult of youth when it comes to choosing party leaders has got way out of hand.  But the point is that good leadership requires experience and acquired wisdom.  By contrast, being a good constituency member of parliament does not really involve leadership skills - the required attributes are commitment, integrity and hard work (none of which Malcolm Rifkind could ever be accused of).  Age is not a barrier to those, either at the lower or upper end of the spectrum.

What many people assume will prove to be a barrier for Danus Skene is the electoral arithmetic in the Northern Isles, which have been held by the Liberal Democrats or the old Liberal party since dinosaurs roamed the Earth.  Curiously, though, as of this moment, the Election Forecast website is suggesting that the SNP have a 52% chance of gaining the seat.  That projection probably won't last, because the individual seat forecasts have been fluctuating from day to day.  But the fact that the SNP are even rated as being in with a shout is startling, given that unpublished constituency subsample data from YouGov is apparently factored into the numbers.

My gut instinct is to say that this sort of prediction ought to make us less trusting of the Election Forecast methodology.  I've been a touch sceptical all along, due to the website's consistent verdict that Plaid Cymru are facing "almost certain seat loss", which seems totally counter-intuitive.  There are any number of reasons for thinking that the forecast of an SNP gain in Orkney & Shetland is equally implausible -

* The SNP finished 41.4% behind the Lib Dems last time.

* Even as the SNP were winning a national landslide in 2011, the Lib Dems held the two Holyrood constituencies of Shetland and Orkney by reasonably comfortable margins.  The SNP failed to take second place in either.

* At a time when the Lib Dems were being slaughtered almost everywhere else in the entire UK, they won the European elections in both Orkney and Shetland last spring by a convincing margin.

* The Yes vote in the Northern Isles in September, although respectable, was probably low enough to ensure that the SNP can't win the seat in May by simply replicating that percentage.

That's the bad news, but are there any grounds for optimism?  Given the scale of the SNP's current poll lead, probably the best pointer is the 2011 Holyrood result.  The European election result is less relevant, because the SNP only had a modest national lead of 3%, and because there was a very low turnout.

This is the combined result for Orkney and Shetland in 2011 -

Liberal Democrats 42.0%
Independents 27.9%
SNP 18.1%
Labour 6.1%
Conservatives 5.8%

I know some of you will protest that the SNP fared considerably better on the list, but for my money the constituency results are a more useful guide to what might happen in May, because they factor in exactly the kind of personal incumbency bonus that Alistair Carmichael can be expected to enjoy.

The obvious hope is that the hefty vote for the independent candidates was a sign of deep disaffection with the Liberal Democrats.  If the SNP become established in people's minds as the only credible challenger this time around (as they surely are), the votes are theoretically out there to defeat Carmichael.  A very tall order, but not impossible.