Lord Ashcroft has released a new batch of Scottish constituency polling. Full details are here. As regular readers will know, national polls in Scotland suggest an SNP landslide with no sign of the SNP lead narrowing as the election approaches. In fact the most recent Scottish polls from YouGov and TNS showed the SNP lead growing. Lord Ashcroft has previously carried out two waves of Scottish polling, both showing the SNP winning in seats that were previously thought very safe.

Across the two previous waves Ashcroft polled nineteen Labour seats, finding the SNP ahead in all except East Renfrewshire and Glasgow North East. He has also polled four Lib Dem held seats (finding solid SNP leads in three and a narrow SNP lead in Ross, Skye and Lochaber) and the one Tory seat in Scotland where he found a tie.

In this latest wave Ashcroft has returned to the five of the tighter races he polled earlier, and polled three more Lib Dem held Scottish seats for the first time. Most of the close races are no longer close – in Glasgow South West (where Labour have a 46% majority) Ashcroft found the SNP 21% ahead. In Paisley and Renfrewshire South, Douglas Alexander’s seat, he found an SNP lead of 11%. In East Renfewshire he found a 9% SNP lead – this is the seat of Labour’s Scottish leader Jim Murphy and one of the two seats where he previously found a Labour lead.

People commenting on the Scottish election seem to fall into two groups – those who expect an almost complete SNP walkover, and those who expect them to merely do extremely well, to take “only” thirty or forty seats. I think the logic of most people in that second group is simply down to the scale of the SNP landslide looking unrealistic – the belief that they can’t be doing that well. I am often the first to advise caution towards polls showing huge shifts, so it’s fair to be sceptical – with a landslide of this scale perhaps the polls could be overestimating the swing… but they are consistent across national and constituency polling, online and telephone, and if they are correct the SNP are headed for an overwhelming victory and Scottish Labour towards something close to wipeout.

The polling in the sole Tory seat in Scotland remains extremely close. In his last poll Ashcroft found a dead heat between the Conservatives and the SNP, this time he found an SNP lead of two points.

Turning to the Lib Dem held seats, last time round Ashcroft found only a five point SNP lead in Charlie Kennedy’s seat in Ross, Skye and Lochaber, that has now grown to fifteen points. He has now additionally polled North East Fife (Menzies Campbell’s seat) where he found a 13% SNP lead and East Dunbartonshire (Jo Swinson’s seat) where he found an 11% SNP lead. Finally he polled Berwickshire, Roxburgh and Selkirk – here he found a 20 point boost for the SNP, which is enough to make it into a three way marginal but not to put the SNP ahead – the poll found the Conservatives ahead on 30%, SNP 29%, LDEM 28%.

Note that the East Dunbartonshire is one of the seat where the Lib Dems have recently released their own private polling (which may or may not be a co-incidence!). Their own polling showed figures of CON 13%, LAB 16%, LDEM 35%, SNP 32%. The SNP are 8 points lower than in Ashcroft’s poll, the Lib Dems 6 points higher. I wrote about the Lib Dem’s own polling at more length here. The primary differences are that the Lib Dems prompt using candidate name, which is fair enough, and ask about how favourably people see their local MP before they ask that voting intention question, a more questionable approach. We shall see which is the better guide. The Lib Dems have not released any of their private polling for the other three Lib Dem seats Lord Ashcroft released polls for today, from which one must draw one’s own conclusions.


ComRes have published a new poll of voting intentions in LD-Con seats in the South West for ITV. Full details are here. The topline figures are CON 44%, LAB 13%, LDEM 26%, UKIP 10%. Given these are all seats that the Liberal Democrats won in 2010 this is a huge turnaround – in 2010 the Lib Dems had an overall lead of 8.5% over the Tories in these seats, now they are 18 points behind, a whopping great swing of 13 points. If there was a uniform swing of this scale across these seats the Lib Dems would lose the lot.

Depressing for the Lib Dems, but wholly at odds with previous polling evidence in these seats. Lord Ashcroft has polled Lib Dem held seats pretty comprehensively, so we actually have constituency polls in 12 of the 14 seats included in this sample, and they paint a very different picture. Compared to the 13 point LD>Con swing in the ComRes poll Lord Ashcroft found an average LD>Con swing of about 4 points.

The difference between these two sets of polling is much larger than can explained by margin of error – they paint a genuinely contradictory picture. If ComRes are right the Lib Dems have collapsed in their heartland and face wipeout, if Ashcroft are right they are holding up against the tide and should retain around half those seats.

Explaining the difference is a little harder. It could, of course, simply be that public opinion has changed – some of Ashcroft’s polling was done late last year… but most of the Lib Dem collapse in support came early this Parliament, so this doesn’t ring true to me. Looking at the rest of the methodology both polls were conducted by telephone, the political weighting was much the same, the turnout weighting not vastly different.

My guess is the difference is actually a quite a subtle one – but obviously with a large impact! Both Ashcroft and ComRes asked a voting intention question that prompted people to think about their own constituency, candidates and MP to try and get at the personal and tactical voting that Lib Dem MPs are so reliant upon. However, looking at the tables it looks as though ComRes asked that as the only voting intention question, while Ashcroft asked it as a two stage question, asking people their national preference then their local voting intention. The results that ComRes got in their constituency question are actually extremely similar to the ones that Ashcroft got in his initial, national question.

This sounds weird, but it’s actually what I’d expect. When I first wrote the two stage voting intention question back in 2008 my thinking was that when people answer opinion polls they want to register their support for the party they really support, not a tactical vote or a vote for their local MP… and even if you ask the question slightly differently, that’s the answer you are going to get. If you really wanted to get people’s local voting intentions, you needed to first give them the opportunity to express their national support and then ask them their local support.

That though, is just the theory. As I’ve written before when writing about constituency polls of Lib Dem seats and marginal polls of Lib Dem battlegrounds, we don’t really have the evidence from past elections to judge what the most accurate methods are. Hopefully we’ll get enough different constituency and marginal polls over the next three weeks to give us the evidence to judge in the future.

Meanwhile tonight’s YouGov poll for the Sun has topline figures of CON 34%, LAB 35%, LDEM 8%, UKIP 13%, GRN 5%


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Lord Ashcroft has a new batch of constituency polls out, this time looking at ten Conservative held seats with majorities of around 9% to 12% – seats that would need a Con>Lab swing of around about 5% to fall to Labour. Full details are here.

National opinion polls are currently showing a swing of around 4 percent from Conservative to Labour, so on a pure uniform swing you’d expect these seats to stay Conservative. The average swing in these polls was 3.5%, so very much in line with that. In practice though there is variation between seats, so Ashcorft did find three seats in the sample where Labour were ahead – Crewe and Nantwich, Finchley and Golders Green and Milton Keynes South. This sort of variation is inevitable, and in terms of the overall impact on seats will be counteracted by seats that Labour should be winning on a uniform swing, but where Ashcroft has found the Conservatives ahead, such as Kingswood and Blackpool North.

It is difficult to analyse the variation between seats too much – in some cases they will be genuine, and we can come up with plausible reasons to explain them (are Labour getting a bigger swing in London, for example, or is Crewe and Nantwich seeing a gradual unwind from the by-election?), but remember each constituency poll is just one poll with the normal margin of error. The fact that a poll in one seat is showing a swing that’s three percent bigger than a poll in another seat may just be normal sample variation between polls, and nothing to do with the situation on the ground.


The worst thing you can do in analysing polls of voting intention is to get excited at polls that show something exciting and different and ignore those that show the same old pattern. Occassionally the unusual poll will herald a genuine movement in public opinion – after all, whenever there is a change, one poll has to pick it up first. More often than not, the unusual poll will turn out to be a freak result, the product of unusual sampling or methods. If there is genuinely a change in public opinion, other polls will pick it up sooner or later, so it’s always wise to withhold your judgement.

Today we have one of those unusual polls, and we have the overexcitement you’d expect. ICM’s monthly poll in the Guardian has topline figures of CON 39%(+3), LAB 33%(-2), LDEM 8%(nc), UKIP 7%(-2), GRN 7%(+3) (tabs). This is pretty odd all round – a storming six point lead for the Tories, up on thirty-nine percent; the Greens and UKIP equal on seven percent.

In the Guardian’s write up they are rightly dubious, and include a welcome caveat from ICM’s Martin Boon about the inevitability of random variation and the sample perhaps being a touch too Tory. I’ll just leave it with the usual caveats – it’s one poll, and an odd looking one at that. Sure, it could be the start of some Tory surge, but if it is we will see it echoed in other polls today…and luckily enough we have at least three of them.

Populus this morning had topline figures of CON 33%, LAB 33%, LDEM 8%, UKIP 15%, GRN 5% (tabs). The Conservatives are up two points (possibly helped by an update in weighting targets), but no big tory lead.

Still to come are the weekly Ashcroft poll and the daily YouGov poll. Come the end of the day, the way to judge where we are is too look at all them as a whole – not fixate on the unusual one.

UPDATE: Lord Ashcroft’s weekly poll has topline figures of CON 33%(-3), LAB 33%(-1), LDEM 9%(+3), UKIP 13%(+3), GRN 6%(-1). Changes are from a fortnight ago – Ashcroft took a week off to avoid bank holiday fieldwork. As with today’s Populus poll, there is nothing here to support the big Tory lead in the ICM poll. Full details are on Lord Ashcroft’s website here.

UPDATE2: Finally the daily YouGov poll for the Sun has topline figures of CON 33%, LAB 34%, LD 8%, UKIP 13%, GRN 6% – a one point Labour lead. Putting all four polls together that ICM poll looks very much like an outlier. Such things are an unavoidable part of polling – and well done to Guardian for reporting it in a heavily caveated way within the context of other polls showing no movement, rather than getting all excited about it.


Lord Ashcroft released a new batch of constituency polls this afternoon, this time returning to ten Conservative -vs- Labour seats where he found a tight battle last time round. Full details are here.

I normally look at the average swing across the groups of seats that Lord Ashcroft polls, but I’d be wary of reading too much into that this time. Because Lord Ashcroft has gone back to the tight races, these are seats that were showing a smaller than average swing before (an average of 2 points from Con to Lab). They still show a lower than average swing of about 2 points…but that’s probably because it’s a sample made up of seats that were showing a lower swing anyway, rather than a sign of a wider pattern.

Most of the seats don’t show much change in the Lab-Con race since Ashcroft previously polled them last year. The biggest differences are in Harrow East, where Labour are now ahead, and in Loughborough and Kingswood, previously tight races but now with healthier Tory leads. Most of the polls showed a drop in UKIP support, but none of these are UKIP target seats and the previous wave of polling in most of these seats was Sep-Oct when UKIP were on a Carswell related high, so this is to be expected. A positive finding for Labour in these seats is that they are ahead in the ground war – on average 71% of people recall being contacted by Labour over the last few weeks, compared to 59% who recall being contacted by the Tories.

Elsewhere, last night’s YouGov poll for the Sun had topline figures of CON 33%, LAB 35%, LDEM 8%, UKIP 14%, GRN 5% (tabs). Nothing particularly unusual, but note that YouGov are now on their election footing, meaning they weight by likelihood to vote in a similar way to ICM and Ashcroft polls (so people who say they are 10/10 certain to vote get a weight of 1.0, people who say they are 9/10 likely to vote get a weight of 0.9 and so on). In past elections this has tended to slightly favour the Conservatives, but this time round it isn’t actually making any substantial difference at all. YouGov have also changed their sampling slightly – taking samples from people who polled in January and February (a period when Labour had a very slight lead in the polls) and weighting them using Jan/Feb vote, rather than party ID from back in 2010.

It also means they are now seven days a week, so we’ll be getting a fresh YouGov poll every night up until the election.