And second, it bothers me that there's 13% of Kippers of which half could easily switch back to the Tories in the voting booth.
I doubt UKIP will win more than two seats in this election - probably east coast Tory seats, in Lincolnshire, Essex or Kent, most likely. But in a GE this tight, this could be crucial. And given the strength of anti-immigrant feeling in some of these seats, and the residual anti-Cameron feeling among the Tory right, this angry vote could well hold firm.
I'd also expect the Green vote to drop, and about a fifth to a quarter of Greens to drift back to Labour.
Given the hundreds of thousands of people who voted Lib Dem in 2010 and who will now drift back to Labour too, I think they have more to gain from the 'soft' votes. Five years of Tory rule tends to focus the mind, in a way that 13 years of Labour government doesn't.
I'd still like Labour to make more of the NHS, with Burnham to the fore.
Cameron's attack on Miliband today is a big mistake. It just highlights all his worst instincts - petulant, presumptuous, light on detail and policy.