DES MOINES, Iowa — Here’s one way of looking at the difference between Mitt Romney and Newt Gingrich.

Romney, the Republican frontrunner and former Massachusetts governor, arrived at the Marriott in downtown Des Moines Thursday around 8 p.m. He walked through the lobby, caught up to some reporters at the elevator and disappeared with them behind the sliding doors.

Gingrich’s bus rolled in closer to 11. He and his wife, Callista, walked along the sidewalk outside the plate glass windows of the lobby, waving to the reporters drinking around small tables in the hotel bar.

View Photo Gallery: Republican candidates are campaigning in Iowa for the Jan. 3 caucuses, with the exception of Jon Huntsman, who is looking ahead to the New Hampshire primary on Jan. 10.

A light round of applause erupted (not from the reporters) when the Gingriches walked in. The candidate happily accepted the invitation of some reporters for some chit chat, but not a drink, and mosied up to the table and held court.

“I love causing R.C. anxiety,” Gingrich joked about his spokesman, R.C. Hammond, who stood anxiously behind the candidate — wishing, perhaps, that his boss would behave a little more like Romney and hightail it to his room for the night.

“I don’t remember any time where you have [this] level of flux and the level of concern,” Gingrich proclaimed to his audience, which included a gaggle of reporters, editors and columnists from The Washington Post and The New York Times. “People who are undecided are passionately undecided, and they’re desperately concerned about the economy. I feel personally very privileged just to be a part of it.”

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