At 1:27 a.m. yesterday, the Guerilla Women of Tennessee weighed in on President Bush's Supreme Court nominee.

"John Roberts: Married to Anti-Choice Org VP," the group's Web site blared. Another site, A Liberal Dose, asked: "Why does John G. Roberts Hate Our Soldiers?"

And Feministing.com made no attempt at subtlety: "Why John Roberts Sucks."

The lightning-quick attacks came after 50 top liberal bloggers held a 45-minute conference call Tuesday night. "On the left, we've always talked about the need to have an echo chamber," says John Aravosis, a Washington lawyer and gay rights activist who writes at Americablog.com. "We believe the right has a whole media network, from talk radio to Fox News to Matt Drudge. The left doesn't have that because the left doesn't play well with others."

This is the first Supreme Court nomination of the Internet age, meaning that liberal and conservative opinion-mongers are already blanketing cyberspace with arguments, facts, taunts, polemics, gossip and electronic links to raw data, hoping to rally the faithful and influence the mainstream media coverage.

The conference call was arranged by BlogPAC, a political action committee that got some of its members on the phone with Sen. Ted Kennedy on the day that Sandra Day O'Connor announced she was leaving the court. The group has also held calls with Senate Minority Leader Harry Reid (Nev.), Sen. Russell Feingold (D-Wis.) and the liberal organizations involved in the nomination battle, including MoveOn, Alliance for Justice, NARAL and People for the American Way.

Kennedy "reached out to them directly to convey the impact that this decision will have on hundreds of millions of Americans, whose last line of defense for their freedoms and liberties is the Supreme Court," says Laura Capps, the senator's spokeswoman.

Such coordination seems to defy the image of bloggers as iconoclastic lone rangers, pounding the keyboards in their bedrooms and basements without regard to interest-group politics. Bloggers, after all, come from all walks of life, building a following on the strength of their words and ability to draw attention from other Web diarists. They have also proven to be a formidable fundraising force, raising $80,000 on Tuesday for a Democratic candidate in a special House election in Ohio.

The purpose of Tuesday night's call was "to agree on where we want to work as a swarm and divide that from where we want to work individually," says Bob Brigham, a San Francisco political activist who runs BlogPAC. (Its founders include Aravosis and Markos Moulitsas, who runs the popular site Daily Kos.) A swarm, in online lingo, is when legions of bloggers jump on the same issue, as when conservative Web sites attacked Dan Rather's CBS report on President Bush's National Guard record.

"We dumped a ton of opposition research on Roberts" after the call, Brigham says. The bloggers also agreed during that discussion to keep hammering on Karl Rove and the CIA leak story.

On the Roberts nomination, though, not all left-wing bloggers are marching in lockstep. Moulitsas wrote that while Roberts has only two years of judicial experience, "I'm willing to hear the guy out. We're not going to get a Ginsburg, but I'd be happy with an O'Connor-style moderate conservative. For all we know (and for all the religious-right knows), Roberts might be that sort of guy."

Jeralyn Merritt, a Denver defense lawyer who writes the TalkLeft blog, told readers that "it's too soon to start opposing Judge John G. Roberts. Most of us knew nothing about him. . . . I don't think it helps that liberal groups are coming out swinging so soon."

Joshua Micah Marshall, who holds a doctorate in history from Brown University and recently moved from Washington to New York, launched a Supreme Court section yesterday on a spinoff of his Talking Points Memo site.

The first entry was from Yale law professor Robert Gordon, who said of Roberts: "He enjoys the kind of respect Kenneth Starr had before embarking on his anti-Clinton crusade, as a safe, sound man, not an ideological zealot like Edith Jones or wacko like Janice Rogers Brown. These qualities are going to make Roberts's confirmation easier. They are also what make him dangerous."

Marshall says liberal bloggers would probably play a bigger role in galvanizing the opposition had Bush picked a more incendiary nominee. "There will be less fireworks than there might have been if it was a more controversial person," he says. "We're trying to get people who have expertise and are interested in writing in this new medium. I have no particular expertise on jurisprudence."

Conservative bloggers, of course, have been out in force as well. Forty-five minutes after Bush's announcement, National Review Editor Rich Lowry posted this reaction: "Roberts is brilliant and solid. He has a good temperament and he's very likable. There's no downside. . . . And Bush has kept his promise to nominate someone in the mold of [Antonin] Scalia and [Clarence] Thomas."

Says Glenn Reynolds, the conservative University of Tennessee law professor better known as Instapundit: "Bloggers are going to be very big on cutting through the slogans to the facts and holding people up against the statements they've made in the past. They're going to make it hard for Democrats and Republicans who took a different position on Clinton nominees than they have on Bush nominees."

But there has been a lack of enthusiasm among some bloggers on the right. "As someone whose professional life has almost entirely taken place 'inside the Beltway,' Roberts has been far removed from the day-to-day concerns of 'fly-over' America," wrote RedState.com. ". . . The nomination of Roberts serves to increase the disillusionment of these traditionalists with Bush's performance in his second term."

One strength of the blogosphere -- its real-time ability to vacuum up thousands of facts -- has been on display with the Roberts nomination. SwingStateProject.com posted excerpts of a 1997 court ruling in which Roberts, representing a pork producer in a clean water case, was accused of making a misleading argument, according to the Web site. The Liberal Dose site (which featured a doctored photo of Roberts making an obscene gesture) pointed to a 2004 ruling joined by Judge Roberts that threw out an award of nearly $1 billion to 17 Americans who said they were abused while imprisoned in Iraq during the 1991 Gulf War.

Aravosis, who helped expose the X-rated past of conservative White House reporter Jeff Gannon, wasted little time. He wrote Tuesday night that Roberts "sounds like a partisan hack" and posted statements from Democratic National Committee Chairman Howard Dean, Planned Parenthood, NARAL, the Human Rights Campaign and People for the American Way.

But Aravosis sees no prospect of his blogging colleagues sticking to a set of talking points. "It's like herding cats," he says. "You can get 40 cats in a room, but you can't herd them."