Killed all support in Scotland first by forming a coalition with the Tories then by backing Westminster in the referendum. All for 5 years of meaningless power where they got laughed at and marginalised by Cameron and his cronies.
Some of the swings have been masseeve, 30k in some cases. Never underestimate the bloodymindedness of Scots
George Galloway's defeat speech "The hyena can bounce on the lion's grave but it can never be a lion" Right you are there Georgie Boy...
I hardly think it was just Scots that voted for the SNP. There is a huge multicultural presence in Scotland. Just look at Glasgow and Aberdeen. The SNP must have got huge backing from non Scots as well.