Best comebacks in the second half of an F1 season

Fernando Alonso has had an error-free run throughout the first part of the season. He has managed to score points at each and every race in 2012 so far. This consistency has elevated him to the top of the drivers championship standings.With four drivers [Mark Webber P2, Sebastian Vettel P3, Lewis Hamilton P4 and Kimi Raikkonen P5] in with a chance of hunting down Fernando Alonso's 40 point lead