This could be Chris Christie's swan song and he left it all on the debate floor. His poll numbers are low and unless he does better than expected in the New Hampshire vote on Tuesday that could be it. With nothing to lose Mr Christie went for the jugular and it was impressive. He showed the mental agility of a former prosecutor and made Marco Rubio look completely flat footed. For Mr Christie the future may now depend on how many people in New Hampshire watched this debate.