(1) There is no way that Obama and the Clintons would be campaigning there unless McAwful really needed them. The fact that they're there/coming demonstrates that McAwful's own polling shows it to be very close.
(2) If you read the article, you will find that the Libertarian candidate is NOT harming Cuccinelli that much. McAwful would still have a 2-point edge if Sarver wasn't there. Some Libertarian-supporters are really just liberal-lite - they will not support a Pro-Life, Anti-Sodomite Normalizer (my own term, which I think accurately describes our view on the issue) candidate.
Sarver = Sarvis