In the latest installment of "Indecision 2012," The Daily Show's ongoing coverage of the presidential race, host Jon Stewart recounted Thursday's tumultuous day of political news.

A PPP poll declared that Stephen Colbert is polling at 13% nationally, Rick Perry announced that he was leaving the race, and ABC News released explosive allegations by Newt Gingrich's ex-wife Marianne.

In an interview to air Friday, January 20, the night before the South Carolina primary, Gingrich's second wife claimed that the former House speaker asked her to participate in an "open marriage" with his mistress.

Gingrich left Marianne just as she was diagnosed with Multiple Sclerosis, a maneuver that echoed his decision to ask his first wife for a divorce when she was in the hospital recovering from cancer surgery. Examining this pattern, Stewart wondered if there's a deeper correlation. "First wife cancer, second wife Multiple Sclerosis," he says, "Can Newt Gingrich be re-classified as a pollutant?"

Watch the clip, embedded via Comedy Central, below: