In my latest round of constituency polling I have returned to Scotland. This selection includes eight seats, including five I have polled before (East Renfrewshire; Glasgow South West; Paisley & Renfrewshire South; Ross, Skye & Lochaber, and Dumfriesshire, Clydesdale & Tweeddale) and three new ones (Berwickshire, Roxburgh & Selkirk; East Dunbartonshire and North East Fife).

I wanted to know whether the SNP surge had subsided in places I had previously surveyed; whether it threatened other incumbents, especially Liberal Democrats; and whether there were any potential surprises in store. The answers are no, yes and yes.

In the three Labour seats, the SNP are further ahead than when I polled them earlier in the year. They have extended their lead from three to 21 points in Glasgow South West, and from eight to 11 points in Douglas Alexander’s seat of Paisley & Renfrewshire South.

In East Renfrewshire, the one-point Labour lead I found in February has become a nine-point advantage for the SNP. However, this seat has a bigger Conservative share than many other Labour strongholds (25 per cent), and I found Conservative voters less likely to say they would rule out voting Labour (64 per cent) than would rule out the SNP (87 per cent). How many Tories will decide to lend their vote to Jim Murphy to stop the nationalists?

Dumfriesshire, Clydesdale & Tweeddale remains a very close contest. The tie I found two months ago is now a two-point lead for the SNP, putting it well within the margin of error and therefore too close to call.

But there is somewhat unexpected comfort for the Tories in Berwickshire, Roxburgh & Selkirk, where I found them a single point ahead in a three-party scrap (Conservative 30 per cent, SNP 29 per cent, Lib Dems 28 per cent). Clearly this seat could go any one of three ways, and all three parties will try to tell potential tactical voters that they are the only way to stop the other two. Labour voters here say they are more likely to rule out the Tories than the Lib Dems, but how much further can the party’s 9 per cent share be squeezed?

Elsewhere on Lib Dem territory, I found the SNP 15 points ahead in Charles Kennedy’s seat of Ross, Skye & Lochaber, up from five points in February. I also found the SNP leading by 11 points in Jo Swinson’s constituency of East Dunbartonshire, and by 13 points in North East Fife, where Sir Menzies Campbell is stepping down after 28 years.

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