Rep. Todd Akin (R-Mo.) had been scheduled to appear Monday on CNN's "Piers Morgan Tonight," part of a media tour to defend himself -- and his U.S. Senate candidacy -- from an explosion of criticism over his controversial comments about rape and abortion.

But when the show opened at 9 p.m. viewers were greeted with an empty chair, where the network expected the embattled congressman to be sitting. The cable network called it a "last minute" cancellation. Morgan, who has struggled to keep viewers against MSNBC's liberal "Rachel Maddow Show" and Fox's conservative "Hannity" show, had been trumpeting the Akin appearance since mid-afternoon Monday.

"You're looking live at the empty chair," Morgan said, kicking off the show. He said an Akin staffer had agreed to the appearance. "We kept our word, I'm here," Morgan said, and jokingly added, "It's a nice empty chair."

He then called Akin "a gutless little twerp."

Other guests, including Rep. Jan Schakowsky (D-Ill.) and journalists Ben Smith and Nate Silver, appeared to discuss the controversy, which has members of Akin's own party leading the call for him to drop out of the race against Sen. Claire McCaskill (D-Mo.) During the discussion, CNN frequently showed in the bottom right corner of the screen a shot of the chair, with a logo reading: "Rep. Todd Akin's Empty Chair."
By 9:25 p.m., Morgan was done with politics. He went to a commercial break alerting viewers: "Up next, my exclusive with Ricki Lake."

Watch Akin's interview with Jaco Report: