Commenting on the Ashcroft poll, Scottish Labour leader Jim Murphy admitted his party was "well behind and has a big gap to close".
However, he added: "But in the end the only people who will benefit from these polls are David Cameron and the Tories.
"It is a simple fact that the single biggest party gets to form the next government."
No, it's not a simple fact. The single biggest party may get the opportunity to try and form a government (although even that is not assured) but it needs to command a majority in the Commons. If Labour and SNP together have enough seats to outvote the Tories (and whatever allies they can scrape together), then Cameron will not be able to form a government.