I recently noted an extraordinary opinion poll which showed that the Scottish National Party had overturned a Labour lead of 10 points and was on track to retain power at Holyrood. Since then, however, several other surveys appear to have confirmed that this was what psephologists call an "outlier" or a "rogue" poll.
The latest TNS-BMRB/Herald poll shows that Labour retains a comfortable lead over Alex Salmond's party and that, while support for the red team has fallen, the SNP has not been the beneficiary. In the constituency section, the poll puts Labour on 44 per cent (-5 since January) and the SNP on 29 per cent (-4), with the Tories up 3 points to 12 per cent and the Lib Dems up 4 points to 11 per cent.
In the regional list, it's a similar story. Labour is down 8 points to 39 per cent, with the SNP down 4 to 29 per cent, the Tories up 2 to 11 per cent and the Lib Dems up 3 to 10 per cent. The Greens are up 3 to 6 per cent and appear to be on track to win as many as six seats.
In terms of the parliamentary arithmetic, these figures would leave Iain Gray with the options of forming a coalition with the Greens or leading a minority administration. A win for Labour in Scotland, followed by victory in the London mayoral election, would be seen as a vital stepping stone on the road back to Downing Street. It looks like this is one early test that Ed Miliband won't flunk.