Of the big four, Quintana is the hungriest, so I'm going with him. Froome is my second pick, but it seems to me that Sky isn't so good about protecting the health of their riders and, like Porte, he's susceptible to suffering from ill-health.

My heart wants AC to do the double with Nibali at his heels.

Right now, AC is the only rider with multiple wins in a single grand tour in the race (as distinct from multiple grand tour wins). Apparently he brings his own hunger. Lord knows he has ridden like a desperate man many times, much to my entertainment.