Back when he was hired, there was a good deal of chatter about just how liberal Colbert actually was. He admitted during his time at the "Daily Show" that he had discovered his liberal politics there, but even some conservatives seemed to respect his brand of comedy, and there was actually relatively little backlash against a guy whose faux conservative alter ego was hardly flattering for the right side of the political spectrum.

And yet, two months into the gig, the 51-year-old funnyman could be alienating real-life conservatives with his persistent brand of lefty wisecracks. And that could be a problem for CBS, which, like all of the major networks, will want to attract Democratic and Republican viewers throughout the next year of presidential electioneering.

In the opening week of November, for the first time since his Sept. 8 debut, Colbert fell to third place in the critical 18-to-49-year-old ratings demographic. Jimmy Fallon, host of NBC's "Tonight Show," has been the runaway leader for most of the fall season, but this was the first time Colbert trailed ABC's "Jimmy Kimmel Live." Last week, it happened again.