Deep in the bowels of the Internet, the swift- boating of Barack Obama is under way.

That's where the presumptive Democratic nominee is "revealed" to be a Muslim who joined Chicago's Trinity United Church of Christ as a Manchurian candidate. This, I suppose, would explain why he took his oath of office for the Senate on the Koran instead of the Bible, as alleged. (That, too, turns out to be a falsehood - he used his personal Bible for the oath.)

No wonder he refuses to recite the Pledge of Allegiance. ("While others place their hands over their hearts, Obama turns his back to the flag and slouches," says an e-mail missive that has more than once found its way into my inbox.)

There is also the bizarre claim that he has been endorsed by the Ku Klux Klan, outdone only by the allegation that Hugo Chávez is funding his campaign for president.

Worse still is the slime being slung at those surrounding the senator. A friend of mine showed me an e-mail last week that crossed 3,000 miles in a split second. It was an attack on Ann Dunham, the senator's mother, who was portrayed as a "communist sympathizer surrounded by Marxist influences."

"When Ann Dunham arrived in Hawaii," the spammer writes, "she was a full-fledged radical leftist and practitioner of critical theory. She also began to engage in miscegenation (interracial relationships) as part of her attack on society." Irrelevant, apparently, to the scribe behind this libel is the fact that the woman died in 1995 from ovarian and uterine cancer and cannot defend herself.

I'm waiting to "learn" that Obama was the one-armed man terrorizing couples on lover's lane those many years ago, or that he put the first alligator in the New York City sewer.

The Internet has forever altered the way we elect presidents and, with regard to rumor and innuendo, for the worse. No wonder that last week, Obama's campaign announced that its war room was preparing itself to instantly attack these kind of smears.

They're so widespread that Obama - on his very first day as the presumptive Democratic nominee - felt compelled to address them during a speech to a mostly Jewish audience at the American Israeli Public Affairs Committee's annual conference: "Let me know if you see this guy named Barack Obama, because he sounds pretty frightening."

This shouldn't be a laughing matter. Here's the real frightening part: Polling conducted in the heat of the Democratic primary in March showed that 13 percent of Americans believed Obama is a Muslim, and 61 percent of those same respondents think he's patriotic. A majority, but one that pales in comparison to the 90 percent John McCain received. I suspect that's because absurdities like Obama's secret Muslim life have already crept into Americans' perceptions.

Connie Chesner is an instructor of communication at Wake Forest University and vice president of research at OTM Partners, a marketing firm. Chesner's research on rumor reaction and corporate communications has been used by the U.S. Air Force and several Fortune 100 companies. I asked her how to stop the spread of Web-driven disinformation.

"It is important to realize," she said, "that no tool or strategy is going to be able to stop a process like this no matter if it is communicated via face-to-face or networked communication."

Responding, she told me, involves three steps: actively engaging the public in rumor collection; quickly addressing the rumors utilizing the same mechanisms used to spread them; and positioning the response in places where people will actually search for it and see it. The goal is to create a "new imbalance of information," in this case, one that doesn't malign Obama's campaign.

Here's hoping Obama's campaign goes on such a fully justified counterattack. It's fine to oppose Barack Obama, but the man is entitled to a fair fight.