Leadership is about doing big things, says New Jersey Gov. Chris Christie, who invoked the phrase in his State of the State address—some two weeks before President Obama voiced the same words to rally the country in his State of the Union address.

Not that Christie thinks Obama stole his line, but the two men have different visions of what constitutes big things. Christie is focusing on budget reform, pension and health reform, and education reform, although "reform" is a euphemistic word for cutbacks. He's convinced the mood has changed enough in the country that the politicians who take on these once-sacred cows will be rewarded.

Speaking to a packed auditorium Wednesday at Washington's American Enterprise Institute, a conservative think tank, Christie at once charmed the audience and disappointed them when he said that short of committing suicide, he didn't know what else to do to convince people he's not running for president. A man of heft and swagger, both physical and intellectual, he has captured the imagination of a GOP searching for a candidate who can hold the party's base and yet appeal to a broader swath of the electorate. "You have to feel in your heart and mind you're ready for the presidency," he said. "I'm not stupid. I see the opportunity. That's not the reason to run."

The way to understand Christie, says Ben Dworkin, director of the Institute for New Jersey Politics at Rider University, "is he has the leadership skills of a powerful prosecutor who happens to be governor. He argues his case in the press, and he stays on the attack constantly." As a federal prosecutor in New Jersey, Christie never lost a corruption case, and there were plenty in a state best known for The Sopranos. His favorite phrase: "Heads I win, tails you lose." Yet he's declined to join other Republican governors and attorneys general in challenging Obama's health-care reform. He says he doesn't have the money to fool around with that stuff right now, and if the law is found unconstitutional, New Jersey will benefit without having to kick in legal fees.

His refusal to join in suggests a degree of pragmatism that is attractive to non-true believers. This is a guy who has focused his message of change, and is clear about what he stands for. This is distinct from Obama's message of change, which meant different things to different people in 2008 and left almost everybody disappointed.

The attributes that have excited Republicans were on full display at AEI. Christie neatly skewered Obama's notion of big things, calling high-speed rail, high-speed Internet access, and a million electric cars "the candy of American politics," not the place where real politicians get their chops in an era of scarce resources. It's not only Obama who took a pass in his budget released this week, Christie said, "the new bold Republicans" aren't saying much either.

“You have to feel in your heart and mind you’re ready for the presidency. I’m not stupid. I see the opportunity. That’s not the reason to run.”

A Quinnipiac poll released this week had Christie at 52 percent job approval, and across the river in New York, Democratic Gov. Andrew Cuomo—"my soul mate," he said—is also cutting deep into spending, and he's got a 77 percent approval rating. Even California Gov. Jerry Brown has gotten with the program, Christie exclaimed.

Christie sees a new zeitgeist of frugality. Soon after taking office in January 2010, he was told the state could not meet its payroll if he didn't act immediately to close a deficit. He impounded money without the permission of the legislature. And when the Democratic legislature threatened a government shutdown, he vowed he would not do as his predecessor, Jon Corzine, had done, and sleep on a cot in his office until the crisis was resolved. "Look at me," he exclaimed, drawing attention to his considerable girth, "I'm not sleeping on a cot." He told the lawmakers that if they engaged in such mischief, he'd get a beer, order a pizza, and watch the Mets.

He likes to tell stories about himself taking on the teachers' unions and the firefighters and the police officers. When he talked to a firefighters' meeting in Wildwood one weekend, they booed him "lustily," he said, and when he got to the podium, he said, "C'mon, you can do better than that—and they did."

Christie's tough-guy approach is working, making him a national figure after just 13 months in office. "He commands the bully pulpit more effectively than any other governor we have seen in modern history," says Dworkin, who predicts Christie will deliver the keynote address at the GOP convention in 2012.

Eleanor Clift is a contributing editor for Newsweek.