He is an outstanding driver. He won the title last year despite having the third best car, which tells you a lot. His win in 2011 was blighted by every other car being completely awful until 3/4 of the way through the year, but 2011 was supremely impressive as well, bearing in mind he didn't lead the championship once until he won it.
If it was just the car, then Webber would be up there too fighting for the title.