Another busy day for polling. We have only one GB voting intention poll today, but from a brand new pollster (later on we’ll have the regular daily poll from YouGov and the ComRes/Mail/ITV poll). However we also have a new Scottish poll from Ipsos MORI, three new constituency polls from Lord Ashcroft and a new poll of Con-Lab marginals from ComRes.

The new GB voting intention poll is from BMG Research for May 2015. It’s an online poll, using the sort of weightings and adjustments ICM use – so weighted by past vote, weighted by likelihood to vote with people who didn’t vote weighted down, and with 50% of people who say don’t know assumed to vote for the party they did last time. This has produced topline figures of CON 35%, LAB 32%, LDEM 11%, UKIP 14%, GRN 3% – full tabs are here.

MORI’s Scottish poll shows, as ever, a huge SNP lead. Topline figures are CON 17%, LAB 20%, LDEM 5%, SNP 54% (tabs). This would be enough for the SNP to win just about everywhere. A measure of just how vast the change has been in Scotland is that we are no longer surprised by polls showing the SNP with huge landslide leads in Scotland – we should be. A thirty-four point lead for the SNP in an area that Labour has consistently won since the 1960s is astounding and appears to be a true realignment in Scottish politics. We end up paying to the rest of the country because England and Wales are on a knife-edge while the outcome of Scotland appears settled, it’s just a question of how colossal the SNP landslide is, but it’s good to sit back occasionally and gawp at the scale of the turnaround in Scottish politics since a year ago.

Lord Ashcroft released three new constituency polls. The first was of South Swindon – a typical Con-Lab marginal seat, but not of any great importance beyond that. At the last election Robert Buckland had a majority of 7.5%, so with the national polls level we’d expect to find Conservative and Labour pretty much neck-and-neck here. That’s what Ashcroft found in his last two polls of the seat, it’s still the case now – a Conservative lead of just one point.

The other two seats are far more unusual affairs. The first is Sheffield Hallam, Nick Clegg’s own constituency. Ashcroft’s previous polling of the constituency has consistently found a very tight race between Labour and the Liberal Democrats (despite the fact that it used to the Tories who were main alternative to the Liberals here). Ashcroft’s poll today shows a Labour lead of one point, so far too close to call. Interestingly comparing the standard voting intention question and the constituency question a quarter of Conservative voters say they will actually vote Lib Dem in Hallam, suggesting significant Tory tactical voting propping up Nick Clegg.

The last of Ashcroft’s polls was in Thanet South, the seat being contested by Nigel Farage. There has been substantial polling in this seat, with recent Survation polls commissioned by UKIP donor Alan Bown showing a solid lead for Nigel Farage and other polling by ComRes showing a tight three way race between Conservative, Labour and UKIP. Ashcroft found a tight race between Conservative and UKIP, with the Tories just three points ahead, but Labour now clearly back in third place – CON 34%, UKIP 32%, LAB 26%. Tables for all three polls are here.

Finally there was a new ComRes poll of battleground Con-Lab marginals. As I’ve written before, the key to understanding marginal polls is to look at how those seats voted last time, what they change is, and how that compares to the national picture. This poll isn’t the 40 closest Lab-Con marginals that ComRes usually poll in their marginals omnibus, but a different bespoke sample of the fifty most marginal Con held marginals with Labour in second place. In 2010 there was an average Conservative lead of 4 points across these seats, while in today’s poll ComRes found a 3 point Labour lead. This is a 3.5 swing from Conservative to Labour, or the equivalent of a national poll showing Labour and Conservative neck-and-neck. Full tables are here

The 3.5 swing is in line with the national swing across all the polls (though a little bigger than the swing in ComRes’s telephone polls). However, I’m not sure that national polls are the right comparison – almost all Lab-Con marginals are in England, and because Labour have collapsed in Scotland the swing to Labour is actually bigger in England & Wales than the national polls imply. I’m going to try write at more length about the different battlegrounds at the weekend, but at first glance it looks to me as if the Conservatives may be doing a little better in the key marginals than across England and Wales as a whole… but Labour are doing a little better in England and Wales as a whole than in GB, so the two factors cancel each other out and the marginals swing is about the same as the national GB swing.

UPDATE: The voting intention figures for ComRes and YouGov are now both out. ComRes’s telephone poll for the Mail & ITV has topline figures of CON 35%, LAB 35%, LDEM 7%, UKIP 11%, GRN 6%. YouGov for the Sun have topline figures of CON 35%, LAB 34%, LDEM 9%, UKIP 12%, GRN 4%.


ComRes have a new battleground poll out, results here, this time looking at 10 Conservative held UKIP target seats. The poll covered some seats that UKIP announced as targets last year but taking out some that no longer seem realistic, like Aylesbury, and adding some obvious ommissions like Castle Point. The overall shares of the vote with changes since 2010 were CON 39%(-7), LAB 28%(+2), UKIP 21%(+15), LDEM 5%(-10), GRN 4%(+4). UKIP have obviously advanced strongly since 2010, but remain in quite a distant third place.

It’s quite hard to know what to make of this poll. For a start, with UKIP coming from a very low base it’s quite hard to accurately predict what their best chances of a gain are – so some seats here like East Worthing and Shoreham probably aren’t in the top rank of UKIP targets. More importantly, with a poll of a group of marginal seats like this we can’t tell what the distribution of the vote is between these different seats. Most estimates are for UKIP to pick up only a couple of seats beyond their two by-election gains (which are not included in this sample), so from this poll we can’t tell whether UKIP have about 21% in all these seats (and hence wouldn’t win any of them), or are doing much better in the more promising seats like South Thanet and Thurrock and less well in the others, meaning they could win some.

I suppose all we can reasonably conclude is that UKIP don’t look like they are about to sweep the board across these seats, it’s impossible to tell from this poll whether or not they are in a stronger position in a minority of them.


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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%


I’ve my usual weekly update to do later tonight or tomorrow morning, but in the meantime a quick note on the new ComRes poll of marginal seats, which has tables here. My heart always sort of falls when I see a marginal seats poll, as I know how people will misinterpret it. Twitter inevitably sees lots of comments about how Labour has a great big lead in the marginals that count, or Labour might be neck-and-neck nationally but they have a big lead in the important marginals – seemingly oblivious to the fact that the topline results and what they mean depends entirely on which marginals you are polling. What could be a bad headline result for Labour in a batch of seats they only just missed out on in 2010 could be an excellent one in a batch of target seats they need for an overall majority. The crucial thing when looking at marginal polls is the swing from the last election, and how that compares to the swing implied by the national polls.

So, using today’s ComRes poll as an example, here’s how you should interpret a poll of marginal constituencies. I expect this will covering old ground for many people, so I hope regular readers will forgive me stating the bleeding obvious in some cases!

The first thing is to look at what the shares of the vote were in those seats at the previous election – without knowing that, any swing or change is meaningless. In the case of ComRes, their marginal seats polls cover the 40 most marginal seats with Labour and Conservative in first and second place. That consists of 25 Conservative seats and 15 Labour ones, with shares of the vote at the last election of CON 37%, LAB 37%, LDEM 18%, UKIP 3%.

The next step is to compare the results of the previous election to what the poll shows. Topline figures in today’s ComRes poll, with changes from the election, are CON 31%(-6), LAB 40%(+3), LDEM 8%(-10), UKIP 15%(+12). From being equal at the last election, Labour now have a nine point lead – the equivalent of a 4.5 percent swing from Conservative to Labour (the swing is the relative change, divided by two).

Now compare it to the national polls. Looking over the current UKPollingReport average it shows a two point Labour lead. Labour were seven points behind the Conservatives in 2010, so conveniently enough this is also a nine point relative change in the lead, and the equivalent of a 4.5 percent swing from Conservative to Labour. In other words, this poll doesn’t show Labour doing better or worse in the marginals, it shows the Con-Lab marginals behaving exactly like the national GB polls suggest they will.

Of course, this is just a single poll of 1000 people anyway, so even if it did show a swing that was a point or two higher or lower in the marginals it wouldn’t be worth reading much into. It could just be sample variation. Looking back over other Ashcroft and ComRes polls in Con-Lab marginal seats we’ve had some showing the Conservatives doing slightly better in the marginals, some showing them exactly the same, some showing Labour doing slightly better. All in all it suggests the swing in Con-v-Lab marginals is very much in line with the swing in the national polls. And that’s to be expected. If history is any guide we might expect the Conservatives to do a little better as most of the battleground seats have new Conservative incumbents, but only by a very small amount – the reality is that Con-Lab marginals do tend to behave in pretty much the same way as the nation as a whole does.


ComRes released their latest poll of marginal seats today. As regular readers will recall, ComRes’s marginal polls cover the 40 most marginal Con-v-Lab seats (25 Conservative held, 15 Labour held). Unlike Lord Ashcroft’s marginal polls (which are actually a series of individual constituency polls in seats that are marginals, which we can aggregate together to get an extremely large sample across a group of marginal seats) ComRes’s poll is a more traditional marginals poll – a single poll of a group of marginal seats, meaning it gives us a measure of those seats as a whole, but has far too few people to tell us anything about the individual seats within that group.

Latest voting intention figures in these marginals with changes from the last time ComRes polled them in September is CON 31%(+1), LAB 39%(-2), LDEM 7%(+1), UKIP 18%(+1). These seats had Labour and Conservative equal at the last election so an eight point lead here is the equivalent of a four point national swing and a one point Labour lead in national polls…pretty much exactly what the national polls have been showing lately (actually if you look at the crossbreaks of the poll they suggest a swing towards the Conservatives in the Conservative held seats, a swing towards Labour in the Labour held seats, but given the sample size of those two groups and that the poll is only weighted at the level of all forty seats I wouldn’t put too much weight on that).

Note also that, judging from the tables, ComRes have switched over to prompting for UKIP in their main voting intention question in this poll – as with their last national poll, it does not seem to have had a major effect (UPDATE – I think this is because ComRes have changed turnout weightings, so that there is a tighter turnout filter for the Greens and UKIP than for the main parties). Tabs are here.

There should be another batch of Lord Ashcroft polls of individual marginal seats later this week.