Christie's pivotal week: Here comes the first 2016 Republican debate

"For him, every week is a big deal. If you slip and you're still struggling to get attention, every opportunity matters," said Julian Zelizer, a professor of political history at Princeton University.

"This is an opportunity to show people what his virtues are ... and try to come away with being something other than that New Jersey guy involved with the bridge scandal," he said. "You want to give off the aura that you can win, that you're a frontrunner."