The Labour vote has changed little or even strengthened. But the Tory and Lib Dem votes are being massacred. Partly to UKIP and partly to Labour.
http://www.ukip.org/poll_results_in_ful ... ource=ukip
Cameron may be going on about "A vote for UKIP is a Vote for Labour".
I have a different statement for you Mr Cameron.
"A deal with UKIP is a massive Tory Victory and one in the eye for Labour and the Lib Dems".
The problem with the whole deal? Cameron does not want us out of Europe and with UKIP at his right arm, he'd be forced to. Although I do believe he has had to face the hard facts over the last two months. Losing Scotland would hurt him exponentially more than losing the EU. Faced with that reality, I believe he's become a bit more pragmatic.
Now he needs to stave off disaster. It is in his hands to keep Labour out of office for the next 5 years. If he fumbles this one he'll pay with a lot more than regrets...