Christie, a Mitt Romney supporter, called Gingrich an " embarrassment to the party " during an appearance on "Meet The Press" on Sunday morning.
"We all know the record," the tough-talking governor said of Gingrich . "I mean, he was run out of the speakership by his own party, he was fined $300,000 for ethics violations. This is a guy that's had a very difficult career at times and has been an embarrassment to the party."
The co-chairman of Gingrich's campaign in Florida, the next state to hold a GOP primary on January 31, said Christie's intra-party attack was "disappointing" and called on the governor to "stop the circular firing squad."
"Far be it from me to tell the governor of New Jersey to focus on his own state, but this isn't a way to begin a campaign in Florida," Alan Levine told The Miami Herald .
Florida is a major prize for the candidates still remaining in the Republican field, and Christie's endorsement of Romney could play an important role, The Star-Ledger of Newark notes . Ed Rollins, a well-known Republican strategist, tells the paper that Christie will be a major benefit to Romney in the state, "by far" more than Romney himself when it comes to campaign appearances. University of Florida political science professor Daniel Smith agrees , noting that "there are a lot of transplants here from New Jersey," significantly more than in South Carolina.
While it is unclear how much of an effect, if any, endorsements will play in Florida, Romney and Gingrich both have jockeyed for the support of former Florida governor Jeb Bush, a popular GOP figure. Bush says he will stay neutral in the race, as does Rick Scott, the current Florida governor and fellow Republican.