The kings of presidential comedy were reunited last weekend  with a little nudge from the chairwoman of the Congressional Oversight Panel.

Five former presidential impersonators from “Saturday Night Live” joined Jim Carrey and the show’s current mock president, Fred Armisen, in a White House bedroom set for a sketch that immediately achieved viral video fame. The experience, Mr. Armisen said, felt like “walking into my television set.”

The first-of-its-kind reunion happened not on the show, but on Funny or Die, the popular comedy Web site (funnyordie.com). It was meant to promote financial reforms, and was partly the product of a conversation between the director Ron Howard and Elizabeth Warren, the chairwoman of the oversight panel. She had said to Mr. Howard that the government must do more to curb troublesome banking and lending practices.

“I said I would try to get together with a few people who might be able to get the word out,” Mr. Howard said in a telephone interview Friday.