Chris Christie is doing well in NH. Will that be enough?

MANCHESTER, N.H. (AP) — Chris Christie is fresh off his 50th day of campaigning in New Hampshire, a state where the New Jersey governor has recently won critical endorsements and his campaign is showing signs of life in the GOP race for president.

[...] Christie's laser focus on the first primary state means he's spent little time building a presence in South Carolina and beyond that could turn a potential victory in New Hampshire's Feb. 9 primary into national momentum.

Christie has taken advantage of that dynamic in recent weeks after the Paris attacks brought national security to the forefront, giving him the chance to employ his tough-talking persona and highlight his work as a federal prosecutor after the attacks of Sept. 11, 2001.

Mike DuHaime, a senior adviser for Christie's campaign, said that while Christie's efforts may not be as visible as others, the campaign is working methodically behind the scenes to lay the groundwork in later voting states.

Ted Cruz tapped a local conservative party organizer to lead his ground campaign in the state, and he has the backing of Dan Tripp, who previously served as state director for Scott Walker's now-defunct campaign.

Christie's most high-profile advocate is Columbia attorney Leighton Lord, one of the governor's college friends who has hosted Christie fundraisers.