Newt Gingrich is closing in on Mitt Romney in New Hampshire, but the former Massachusetts governor still leads the former House Speaker by 16 points, according to the latest Marist poll:

Here is how the contest stands among likely Republican primary voters including those who are undecided yet leaning toward a candidate in New Hampshire:

• 39% for Mitt Romney
• 23% for Newt Gingrich
• 16% for Ron Paul
• 9% for Jon Huntsman
• 3% for Michele Bachmann
• 3% for Rick Perry
• 2% for Herman Cain
• 1% for Rick Santorum
• 4% are undecided

As you can see from the poll, Herman Cain’s decision to suspend his campaign (and his reported decision to endorse Gingrich today) probably won’t have much of an impact on the New Hampshire race, since Cain is only at 2 percent. But some undecided voters may be influenced by the Union-Leader, which recently endorsed Gingrich and has been taking regular shots at Romney from its editorial page.

But with just one month until the Iowa caucus, one obstacle Gingrich will have to tackle is his lack of organization. While Romney has been carefully crafting his cross-country operation for over a year, Gingrich is only now rushing to put one into place. the New York Times reports:

Where volunteers for Mr. Romney have gathered voters’ signatures to be on the ballots of Alabama, Illinois, Indiana, Vermont and Virginia, Mr. Gingrich’s campaign is only beginning to activate volunteers in those states.

And adding to the specter of a drawn-out battle is a change in the delegate selection process, which could make the contest a Republican version of the protracted 2008 Democratic primary fight between Barack Obama and Hillary Rodham Clinton, which was not resolved until all states had voted.

A drawn-out primary race would almost certainly favor Romney, who has the strength and organization on his side. Gingrich’s long political background and history of chattiness could also work against his favor in a long primary season, because it will give his opponents and the media a huge amount of fodder to attack him with during the race.