The hosts and their guests have had smart, surprising debates about deficit reduction (in a recurring challenge to legislators called “Name Your Cuts”), overseas wars and airport security. But the show has been marred by tensions behind the scenes about the balance between the hosts, especially in recent weeks as the scales have tipped more in Mr. Spitzer’s favor, according to several CNN employees who spoke on condition of anonymity because they feared losing their jobs if they spoke publicly.

The tensions spilled into public view last week when the Page Six gossip column in The New York Post said Ms. Parker had stormed off the set in early November. Asked about that claim, Ms. Parker said, “I don’t storm. I saunter.”

She acknowledged that there was some “editorial and political tension,” but cast it as a normal part of television production. “That’s how human beings are made,” she added.

Mr. Spitzer put it this way: “I’ve seen tension in my life — conflict, tension, acrimony — and I haven’t seen anything here that comes close to what I’ve seen.”