I like how no ones mentioning the Lib Dems.
Its exactly this sort of ignoring of them, that allows them to make gains. No one considers them a viable threat, Tories and labour batter the shit out of each other and ignore the Liberal democrats. Ignore seats they consider safe and the other party won't engage with, Liberal democrats soop in using some very clever tatics largely revolving around actually engaging with the public (lot of this is ramping up now as a matter of fact). Allowing them, then to pick up a seat here and seat there. There biggest problem has and always will be gerrymandered seats (more than they have never been in the position to gerrymander unlike labour and the tories) and the geographically distributed nature of their support. Its none the less something like 33% tory, 33% labour, now at worst 18% liberal democrats. One of the largest historical criticisms has been the lack of political control beyond a local government level, that narrative is now gone.
And if you think their going to be either Labour or the tories focus at the next election... I would have to ask why you thought that.
In 2 1/2 years the most negative thing about them is still likely to be 'uhhh Nick Clegg, tuition fees BADDDDDD, I RETARDED VOX POP' and 'uhhh sell outs'. Hell, most of the negative comments about them, are largely coming from shit comedians and pissed off eternal students.
For despite the drum banging of the NUS. Hah. students as a sustained and credible political force. Want that, go to France. Here for all the marches, do they turn up in droves on election day. Nope.
Frankly people who write the Liberal democrats off, don't really get how the system works. I'd be surprised if they didn't pick up a seat or two next election. Which means unless the tories face a wash, which... they just might, just not 100%. We get the whole coalition go around again.
Worse can scenario, loose maybe 5-6 seats. Though this depends on militant NUS elements getting the vote out and getting it sustainably to labour, which... yeah.. good luck with that.