No idea, for all that say Alonso has had the worst car, while I agree he's had a car capable of going out and winning by beating the RBR/Mclaren on tract, he's had a car capable of picking up the win when one of the others drops out the most often. For all the good drives, he's picked up plenty of points via other cars failing, which doesn't really scream of deserving either.
Could decide its Hamilton, because he's been screwed out of the most points and for me has done some of the best driving when not in the lead, closed up on those ahead like in Canada and taken the lead which really hasn't happened much this year.
I think all in all with the three of them, I think Hamilton would be furthest in the lead if his team/car didn't fail so often.
Vettel, I can't look past how much that RBR breaks the spirit of the laws on purpose. Passes flexi wing test by building a wing that tilts instead of flexing, with multiple rules based around maintaining a minimum height, minimum flex, its inherently completely against every idea the rules meant to enforce, but because it passes one test, its "legal". The car has far far too big an advantage when its fast, when its been the fastest, which for me is now the most often of any car this season its been far far faster than the next best car. He's had the least tough races to take points in and also gained plenty of points from others dropping out.