Imagine if Dan Rather and CBS News had reported that President Bush as governor of Texas had an affair with a beautiful young intern, that her dad was furious over his "sleazeball" behavior, and that she had fled the country to avoid reporters hot on her trail.

Then, suddenly, the mystery woman emerges from her African sanctuary to denounce the rumors as lies in no uncertain terms, and the story, built wholly on secondhand comments and pure speculation, collapses into nothingness.

What would happen?

That’s easy.

Dan Rather's head would be on a pike in the middle of Rockefeller Center today. Torch-bearing radio talk show hosts would be howling. The Net would pulsate with the bile and bilge of lucianne.com, townhall.com, worldnetdaily.com. and other red-meat conservative sites. The denunciations would go on for weeks if not months. The right would be bug-eyed in full banshee frothing.

LIBBBERRALLLLLL BIASSSSS!!!!!

Now imagine if the shoe were on the other foot. If Matt Drudge, the right’s über online journalist-scourge, the man who famously first linked Bill Clinton's genetic residue to Monica Lewinsky's stained blue dress, had smeared John Kerry with a bogus sex allegation. What would happen?

Nothing. Nada. Not a darn thing.

This was precisely the outcome this past February when Drudge breathlessly -- and wrongly -- announced that Kerry had a dalliance with a young journalistic intern. What, you never heard of his screw-up?

Of course not; Drudge's mistake was quickly consigned to the memory hole of public discourse. Today, Drudge continues on his merry way as the Web's must-read political commentator (more than a million hits a day), fanning the flames, no less, for Dan Rather's firing for having publicized those allegedly bogus Bush military records.

This is rich in irony, of course, but more important, it reveals an important fact: More often than not, it's the conservatives who steer news coverage, playing up stories that benefit them, burying those that hurt the cause.

If only Dan Rather had breathlessly reported in a self-described “world exclusive” that “CAMPAIGN DRAMA ROCKS DEMOCRATS: KERRY FIGHTS OFF MEDIA PROBE OF RECENT ALLEGED INFIDELITY, RIVALS PREDICT RUIN."

If only he had gone on to say that “Intrigue surrounds a woman who recently fled the country, reportedly at the prodding of Kerry....”

What a fine and sleazy narrative! It was plausible if not almost believable. Drudge masterfully kept the non-story afloat for more than a week. He’d provide periodic updates and link to newspaper and online stories that were usually just stories about the rumors and how the Kerry’s campaign was supposedly faltering because of those same rumors.

Drudge asserted (sans evidence) that Time, ABC News, and the Washington Post were in hot pursuit of Kerry’s relationship with the former AP reporting intern Alexandra Polier. “She would joke that she was dating the next president of the United States, says a source,” Drudge reported. “Polier’s flippant remarks and flirtatious manner, according to friends, fueled the intrigue.”

Rush Limbaugh spent an hour on his show explicating the budding Kerry scandal for his 10 million listeners. Wesley Clark, one of Kerry’s Democratic presidential rivals, stupidly told reporters that “Kerry will implode over an intern issue,” which triggered even more blog action and news stories from as far away as India, Australia and England.

There was a wonderfully circular dynamic to all this, the journalistic equivalent of a perpetual motion machine. It only crashed to earth when Kerry categorically denied he had an affair: “It’s rumor. It’s untrue. Period.” Polier, who was visiting her fiancé in Kenya, issued her own unequivocal denial, while her parents (including her Republican dad) publicly praised Kerry. The candidate’s supposedly struggling campaign won the Wisconsin primary.

And Drudge's great screw-up, and the right wing's complicity in furthering it, was quickly forgotten.

Credit Polier for writing what may turn out to be one of the lasting pieces of reportage in the 2004 campaign: Her role as the star freak show in the media circus.

Writing in the June 7 New York magazine, she told how she was a political junkie who wanted to work in journalism. She met Kerry at an economics conference in Switzerland and over a drink told him about her hopes; he urged her to contact his campaign back in the States. Soon she was dating Kerry's’ finance director and occasionally socializing with the candidate.

A not-unusual story for someone who's young, pretty, self-assured, well educated, well connected and terribly ambitious. And a good writer, it turns out.

Polier’s stroke of genius was not just to bemoan her fate as media road kill, but to reconstruct the story. She interviewed the reporters who kited the story, even Drudge, and traced the rumor’s origins back to an obscure blogger (the "Son of Liberty") and a onetime school friend who worked for a Republican lobbyist and who apparently embellished her water cooler tales of Polier taking calls from Kerry.

Drudge admitted: "I should have had a sentence saying, 'There is no evidence to tie Alex to John Kerry.' I should have put that in."

David Frum, a prominent conservative strategist, had chatted about the affair as if it were fact. "I regret it," he told Polier. "I heard it gossiped about but didn't do anything like reporting. I joked about it on the Internet in a way that I would at dinner. Then I learned the Net is like print, not like dinner."

In the print world, a screw-up of that magnitude would be a firing offense. The reporter’s head would be lopped off as an object lesson in the necessity of checking facts. In the world of online journalism, or what passes for journalism, this would be no big thing. Just classic agit-prop in the service of the still ascendant conservative agenda.

All together now: CONNNNSERVAAAAATIVE BIASSSSS!!!!!

Marc Eisen, eisen@isthmus.com, is editor of Isthmus. He checks the Drudge Report a half-dozen times a day.