Oh cool, so I guess we don't need to run the election then?
Well that would be a welcome start. Don't you feel as though your vote is actually of use voting for the Greens than not voting at all? Surely if Labour are going to win, then by not voting for them you're effectively voting for them?
First past the post makes it unlikely that secondary parties will actually get in to power, but Labour's big problem is that the left vote is split a heck of a lot more than the right.
Tory voters won't turn out in this election, but the left will and if they're not happy with Labour then they have choices. If the left vote is split enough, rather than the turnout being low, then it's not a foregone conclusion or a landslide. You're talking a possible Labour minority, a possible coalition, or heck even a Tory minority.
At this moment in time it's all to play for, and it's better to play than shout at the television about how everyone got it wrong apart from you and this is why we can't have nice things, or how it was all inevitable.