Megyn Kelly: Soon to be killing Bill O'Reilly in Fox News ratings? "The Kelly File" -- with former daytime host Kelly carving up the issues of the day -- delivered big returns for Fox News Channel in its second outing at 9 p.m. Tuesday, according to Nielsen. Kelly rounded up 2.8 million total viewers, which dominated the time slot over MSNBC's Rachel Maddow (1.1 million) and CNN's "Piers Morgan Tonight" (590,858). That was a huge increase over the 2.1 million "Kelly File" saw for Monday's premiere. More important, Kelly was within hailing distance of the man who has dominated cable news for more than a decade: O'Reilly (3 million). In fact, Kelly decisively beat O'Reilly -- and everyone else -- in the crucial adults ages 25 to 54 demographic, which is what most advertisers care about in the TV news business. If the current trend keeps up, Kelly, and not O'Reilly, will soon be the No. 1 person in cable news. Even though "Papa Bear" O'Reilly and Kelly theoretically wear the same Fox News jersey, this is a seismic event for several reasons. There's a generational shift going on. O'Reilly still draws the biggest audience in cable news, as shown by his lucrative side business of books about the deaths of iconic figures -- "Killing Lincoln," "Killing Jesus," etc. But at 64, he's beginning to feel like yesterday's news. Kelly is 42 and so attractive that entire articles have been written mooning over her various virtues, physical and otherwise. One thing O'Reilly has never been accused of is being a smokin' babe. Meanwhile, Kelly's ascension may signal a deemphasis of opinion in prime time. O'Reilly made his name with brash opinions and vigorous takedowns of guests he disagreed with. Kelly favors a different approach, telling Meg James of the Los Angeles Times: "I'm a news anchor, I'm not an ideologue. Fox News chief Roger Ailes put Kelly in the prime time lineup to bring new vitality to the network. So far, the gamble appears to be working.