Mr. Clinton, he said to knowing laughs, “was far from the perfect candidate.”

With his wide-ranging talk, as a guest of the Economic Club of Chicago, Mr. Christie seemed determined to reassert himself as a Republican standard-bearer, despite the imbroglio over accusations of political intimidation that awaits him back in New Jersey.

After weeks of subdued and somber appearances, at which he spoke of soul-searching and self-flagellation, it was the old Chris Christie who emerged inside a ballroom at Chicago’s Sheraton Hotel and Towers: at once sharp-tongued and philosophical, boastful and self-deprecating, political and personal as he held an audience of about 1,500 in his thrall.

He boasted of his daughter Bridget’s aggression on the basketball court (“it’s almost embarrassing”), and he cracked wise about how little time his son Andrew, a student at Princeton University, spends in class. “The more you pay,” he said, “the less they go.”

But the contradictions and complexities of Mr. Christie were never far from view.

He took pains to explain that it was “irresponsible” for him, a mere governor without access to top-secret briefings, to criticize Mr. Obama’s approach to foreign policy (earning warm applause in the process).

Moments later, he seemed to disregard his own mantra, saying: “I do detect some confusion in the world about who we are and what we stand for. That needs to be clear.”