Ricardo Rodríguez did not arrive lightly at his decision to become a cartoon character.

Before stepping into the Times Square hurly-burly of Elmos, Minnie Mouses and Batmen who pose for photographs and then coax customers for tips, Mr. Rodríguez spent a week studying the competition. He analyzed tourist behavior. He calculated potential earnings. And in the absence of anyone masquerading as a certain Nickelodeon star, he spotted an opportunity.

Thus was born SpongeBob SquarePants Rodríguez.

On his first day he made $80 in five hours, a better rate — and more interesting work — than the series of temporary jobs he had held since immigrating to the United States from Ecuador in March.

“I never imagined I’d be doing this,” said Mr. Rodríguez, 35, during a break on a recent evening, his angular foam costume perched on the sidewalk outside the Nasdaq building. “But if you think about life as a rich experience, the money will come.”

Market advantages among the street performers of Times Square have been hard to come by lately. In recent years, these costumed characters have become ubiquitous, replacing the more sordid denizens of decades past. To some critics, they are little more than colorfully attired panhandlers and a chronic nuisance at the Crossroads of the World.