His tenure has been characterized by fruitful but sometimes fraught relationships with Democrats - relationships that, he says, are on the mend.
And it has been marked by flirtations with higher office that ended with his endorsing Mitt Romney and becoming a key player in this year's presidential campaign. He's rallying the Romney faithful Sunday evening in New Hampshire.
But it is the 49-year-old former federal prosecutor's personality - captured in candid and occasionally confrontational moments on YouTube - that has fueled the Christie phenomenon.
Word has spread that "the guy's fearless," said Adam Geller, a Republican pollster who worked on Christie's 2009 campaign.
"He is not consumed the way other politicians are consumed with poll numbers, with what are people going to think," Geller said.
That has not always played well. New Jerseyans have told reporters and pollsters Christie is a "bully" and "arrogant."
In retrospect, Christie says, he has made a few "tactical" mistakes in saying things the wrong way, thereby giving fodder to opponents.
That is part of the reason he grades his tenure a B-plus.
Little 'margin of error'
Christie said he tries to maintain "spontaneity" while avoiding statements such as the one last year when he advised reporters to "take the bat out" on 76-year-old Sen. Loretta Weinberg (D., Bergen). The phrase was not intended literally, but Democrats said it condoned violence against women.
Although Christie said he stands by the point he was trying to make - that reporters should write about her income from a public pension - "I think if I had to do it all over again I wouldn't have said it."
"I don't know if [such statements] change people's impressions of me, but they distract from what I'm trying to get done," he said. "And I can't afford that. I don't have a lot of margin of error in this job being a Republican in a Democratic town."
That may be true, but Christie has nonetheless been resourceful in navigating Democratic waters.
For example, he has worked with Senate President Stephen Sweeney (D., Gloucester) to enact several historic measures - including pension and health benefits changes for public workers and a 2 percent property-tax cap.
The relationship soured over the summer after Christie blindsided Sweeney with a series of cuts to funding for the poor. Sweeney cursed out Christie in a newspaper interview, and the men did not speak for weeks.
But a few days after Christmas they had a four-hour dinner, alone, at one of Sweeney's favorite spots, Filomena's Lakeview in Deptford. Mostly, they talked about their families and told "old war stories," Christie said. They spoke little about work.
"I don't know how he'd characterize it, but I'd say at this point we're friends," Christie said, adding that he hopes they remain friends after they leave office.
"I like the guy a lot. I think he is brave in a lot of the things he has done politically, and he has always been honest to me. He has never made a promise to me that he hasn't kept. And in politics, that's a pretty good guy to be friends with."
Sweeney said: "We fight a whole lot, but it doesn't mean I don't like the guy."
One point of contention? Sweeney thinks Christie's top accomplishment has been "protecting millionaires."
Sweeney nonetheless paid the dinner tab - in cash.
Christie's relationship with the state's other most significant elected Democrat, Assembly Speaker Sheila Oliver (D., Essex), has had similar ups and downs.
Oliver supported the legislation that increased workers' pension and health-care payments despite opposition from the Democratic base of public unions. But when word leaked of how Christie boasted that Oliver asked for his help if Democrats tried to boot her from her leadership position, Oliver questioned whether the governor was "mentally deranged."
Since that point, the two are "developing more of a relationship," Christie said.
"And that's taken a bit of a longer period of time, but I think we're going to get there as well," he said.
He has met with Oliver three times in the last month, including on Thursday, when they spent 20 minutes of their hour together talking about their personal lives.
In speeches, Christie often contrasts his style with that of President Obama, who is reportedly not close with congressional Republicans. "You've got to have human relationships," Christie said.
Oliver described it this way: "The governor and I have had two years during which time we've had to get a sense of our personalities and our styles. . . . And it has moved to a better place."
On an "infrequent" basis Christie speaks with George E. Norcross 3d, an unelected Democratic political player and chairman of Cooper University Hospital, who has aligned with Christie on education issues.
A few days after the legislative elections, in which Democratic incumbents went undefeated in South Jersey, Christie said he called to congratulate Norcross.
"I'd call it a cordial business relationship, but nothing more than that," he said. "He's an important guy in the state, so, sure, it's an important relationship."
Despite Norcross' support, the "year of education reform" that Christie had promised for 2011 did not pan out.
"I had the sense that politically, the [Statehouse] was exhausted after pension and benefit reform, then [legislators] had an election, so maybe it was too much for me to ask for them to do it," Christie said.
He says his education policies will address the achievement gap in cities like Camden. Asked if the state could take over the Camden school district this year, he said: "I hope not."
Regarding public safety in Camden, Christie endorses a regionalized county force to take over the city police department, but he says he has not seen the specifics. The attorney general, he said, will look at the plan before it goes into effect.
Although no other towns in the county have agreed to join, Christie said that when the city becomes part of the force "that will give political courage to other towns saying: 'You know what? We can save money doing this, too.' "
Grayer now than before he came into office, Christie said he has matured and become more organized with his time so he can both work and spend time with his four children. It helps, he said, that he needs only four or five hours of sleep per night.
"When you get a significant amount of responsibility and you take it seriously, it matures you, if you're a good person," Christie said. "And I think I am."
Contact staff writer Matt Katz
at 609-217-8355, firstname.lastname@example.org, or @mattkatz00 on Twitter. Read his blog, "Christie Chronicles,"