I actually think that, over the course of the last month, Ed has become damaged goods.
The narrative even within the party seems to have gone from 'He means well and could surprise people' to 'When's his next misstep due?'.
The irony in the events of the last month seems to be that Heywood has scared the PLP so much that it's damaged Ed more than Clacton's damaged Cameron. There's a lot in saying that the Tories expected to lose Clacton.
There's a bit of fear that 2010 wasn't Labour's floor. That it could sink further below what it got. The polls themselves don't show a great deal of CON to LAB switchers. There's an over-reliance on Lib Dem 2010 voters leaking back to Labour where it counts and an over expectation that UKIP won't damage them. What you could find is that in traditionally suburban seats like Bolton West that Labour hold by a gnats wing, the Lib Dem voters who have stayed with them from 1997, could leak disproportionately back to the Conservatives, gifting them the seat from Labour. There is also a problem in Scotland, which while it may be fleeting, currently shows Labour performing as badly (and the SNP performing as well) at Westminster as they are at Holyrood, with voting intentions at 2011 levels. While Labour are maxed out in Scotland, they can't really afford to fall back.
I've heard it stated before, that Labour's vote is much more efficient the Tories'. Parties with relatively efficient votes tend to get screwed as their support declines because small wins turn into small losses. e.g. Bloc Quebecois 2011. With that in mind, how low would Labour's support have to go before their vote distribution would start harming them?
