David Doss, senior executive producer of “Election Center,” said that Ms. Brown can be as relentless with colleagues as she is with a reluctant guest.

“ ‘Come on, Candy, come on, John, come on, Roland,’ ” he said, stringing together Ms. Brown’s recent on-air proddings to Candy Crowley, John King and Roland Martin, all of CNN. “She is horrible to work with,” Mr. Doss added, laughing. “She challenges everyone.”

In response to the many viewers who posted messages at cnn.com complaining that her “Free Sarah Palin” monologue was unfair to the McCain campaign, Ms. Brown cited an array of other reports on “Election Center”  many of them by Tom Foreman and Joe Johns under the heading of a “No bias, No bull report card”  that had been skeptical of Senator Barack Obama, Mr. McCain’s Democratic rival.

For example, after showing a clip on Sept. 22 in which Mr. Obama asserted that “if my opponent had his way, the millions of Floridians who rely on it would have had their Social Security tied up in the stock market,” Mr. Foreman made the following observation: “Well, Campbell, if retirees are afraid John McCain wants to take away their checks as Obama suggested, they need to know that it’s just not true.”

Ms. Brown, 40, does concede that the kind of journalism she is now doing at CNN is less traditional than that taught at journalism schools  or, for that matter, practiced by her previous employer, NBC, which assigned her to cover the Bush White House and, later, to be a host of “Weekend Today.” (She had been regarded as a candidate to succeed Katie Couric as a host of “Today,” and left the network several months after the job went to Meredith Vieira.

“As journalists, and certainly for me over the last few years, we’ve gotten overly obsessed with parity, especially when we’re covering politics,” Ms. Brown said. “We kept making sure each candidate got equal time  to the point that it got ridiculous in a way.”