This has happened before, but I thought it was worth noting that in the regional breakdown in last night's UK-wide YouGov poll, Scotland was the place where Labour had its lowest vote share.
Labour's vote share by region :
North of England 57%
South (excluding London) 32%
That may well be a sampling quirk, and tonight's poll may show Scottish Labour in a healthier position. Nevertheless, the fact that such results are even possible is an illustration of how fundamentally the politics of this country have changed.
For what it's worth, there were two polls yesterday (YouGov and Ipsos-Mori) that showed the SNP ahead in the Scottish subsample, in spite of the fact that Labour were well ahead throughout the UK. And that of course is for Westminster voting intention - the Nationalists' weakest suit.