Actually Santorum has overcome more than anyone in the race. He started out without much hope.
He is the only threat left to Mitt Romney and has beat him in quite a few states. He knew what he was up against and still managed to keep trucking on.
I would call that quite an accomplishment.
In these times the man we need for president is someone who can overcame a coordinated program of continual lies and still stick to his principles and articulate a strong patriotic message. He needs to be able to take all they can dish out and still not give in an inch on principle. He must be intelligent, principled and courageous.