1. Labour voters stay at home. That happened in 2001, but they stayed at home in constituencies with whomping great majorities so it didnt matter.
This will probably happen again, but to a lesser extent and still in the safe seats. I think there might be a problem getting out Tory voters as a lot of the base is relatively unimpressed with the Tory party right now.
Well, this'll happen, but it won't be enough to swing many seats, only about 15 to 20 at most. The rest they'll have to do some leg work for.