Just how smart is Mo Rocca, the Zeliglike humorist who provides such a positive role model for geekdom at large?

He has been able to recite the capitals of the world since he was 8 or 9. Much of modern pop culture swirls in his head, and Rocca can dispense it with speed and precision. He is multilingual and a close student of U.S. presidential history — especially the quirky bits. He is on the radio, on television, onstage, online and in print.

The true measure, however, might pertain to the world of food. Rocca has embraced it with all his intellectual rigor — right up to the point of cooking it himself. He’s smart enough to get others to do that for him, on a TV show that has just been picked up for its second season on the Cooking Channel ( My Grandmother’s Ravioli).

“The stomach is the portal to history, to science, to family,” he declares. “I don’t open my oven. But I have become good at chopping.”

Rocca began doing commentary on CBS Sunday Morning in 2006 and prefers his current gig as contributor of segments on, say, the influence of Mexican hot dogs and the history of Caesar salad.

“I ran out of opinions,” he deadpans. “It was unsustainable. I like being the Charles Nelson Reilly of food.”

The reference to the late comedic actor seems off the cuff. But at 43, Maurice Rocca chooses his words and imagery with purpose. Reilly was a lively presence on many TV talk shows and game shows in the ’60s and ’70s, a campy quipster with a love of theater and a background in children’s programming.

Some adults maintain few vestiges of their childhood selves. In Rocca’s case, traits were established that delight his colleagues and cause his fans to gush on Twitter: He is driven by curiosity, a natural kibbitzer, a gentle prankster, unaffected by fame.

“He is fascinated by things the average person wouldn’t even think about,” says Vance DeGeneres, a friend and fellow Daily Show alum. “I can’t think of anyone else like Mo.”

Rocca spent formative years watching those Reilly-era TV shows at the modest family home in Bethesda, Md., where his Colombian-born mom, Maria Luisa “Tini” Rocca, still lives. When he wasn’t memorizing the almanac or working his way through the set of World Book encyclopedias, he was finding ways to make his family laugh. There were tap dancing lessons, even a little ballet, and he entertained classmates all along the way, including Harvard (Hasty Pudding president).

After post-graduation study of kabuki theater in Japan, he moved to New York in 1992. Soon enough, road-company theater gigs and friends who knew friends welcomed him into a world that, in turn, offered opportunities in television.

Rocca says he “really learned to write” when he worked on Wishbone, a children’s show on PBS about a Jack Russell terrier whose daydreams followed story lines of classic literature.

“I was always good at parodies, but making Aldous Huxley’s Time and the Machine accessible to 6- to 11-year-olds requires great effort,” he says. “A plot needs to keep moving forward. Shouldn’t all narrative do that?”

His unlikely career in food television began eight years ago, when a friendly acquaintance with a Food Network exec led to 10 appearances as a guest judge on Iron Chef America.