If this election doesn't go Labour's way, the seeds of Ed Miliband's downfall could well be traced back to the Scottish Referendum.
Labour might have been on the winning side then, but a resurgent SNP was one of the unforeseen consequences, and one that is causing Labour a good deal of pain.
So much so that our new ITV News/ComRes poll of all Labour's 40 Scottish seats shows a 19-point swing from Labour to the SNP.
What that means - translated into projected votes - is that the SNP would be on course to snatch 28 of Labour's seats, leaving them with just 12 MPs in Scotland.
That's 28 seats that Labour would then have to make up elsewhere. And with the election this close, that could be enough to put Ed Miliband's hopes of an overall majority out of reach.
"You don't blow the whistle on the match before the game is over" - the Labour leader has said of his party's position in Scotland - true, but at the moment it's the SNP making all the running.
An ITV News/ComRes poll of all Labour's 40 Scotland seats shows:
Swing from Labour to the SNP
Translated into projected votes this means:
Seats Labour would lose to SNP
Leaving Labour with:
MPs in Scotland