At a time when centrism has become a dirty word in some Democratic Party circles, hundreds of the party’s avowed moderates are convening in Denver this weekend to discuss their agenda for this fall’s election and the presidential contest in 2008.

The annual meeting of the Democratic Leadership Council, a group that came to prominence in connection with President Clinton’s electoral victory in 1992, takes place as the organization has become a lightning rod for criticism from liberal Web-based activists known as the netroots.

The Denver gathering is scheduled to hear from the putative Democratic frontrunner for 2008, Senator Clinton, as well as other possible contenders such as Senator Bayh of Indiana, Governor Vilsack of Iowa, and Governor Richardson of New Mexico.

A former Congressional staffer sharply critical of the group, David Sirota, said the speeches to the group will carry some political cost. “Among a certain segment of voters, it’s absolutely, positively negative. It’s radioactive,” Mr. Sirota said. “Candidates should at least consider the radioactivity.”

The tension dates back to the last presidential race when council officials threw cold water on the populist, Webdriven campaign of Howard Dean. Dr. Dean, who is now chairman of the Democratic National Committee, derided the council as the “Republican wing of the Democratic Party.” A sharp-tongued aide for a Dean rival told the New Republic that the Vermont governor’s Internet-savvy backers resembled the grotesque denizens of the “bar scene from ‘Star Wars.'”

The conflict between the two camps is so intense that when Mrs. Clinton appeared before the council last year and called for a halt to the internecine fighting, bloggers unleashed attacks on her that are still reverberating. A newspaper report in May that Mrs.Clinton hoped to create a unified Democratic agenda under the council’s aegis received two reactions from a leading liberal blogger, Markos Moulitsas of DailyKos.com, “LOL,” shorthand for “laugh out loud,” and “DOA,” meaning “dead on arrival.”

Since Mrs. Clinton took an official role overseeing the council’s issues agenda, the group has tried to step back from the poisonous fight with the blogosphere. However, the DLC’s president, Bruce Reed, said the group is still pressing the Democratic Party to reach out to the political center.

“If we’re going to be a majority, we have to get bigger. We have to compete in places like Colorado and the Southwest where it’s been an uphill battle in the past,” said Mr. Reed, a former domestic policy adviser to Mr. Clinton. “We need to be winning over independents and disgruntled Republicans, not just talking amongst ourselves.”

The council was founded in 1985 by Democrats determined to confront a party establishment controlled by union leaders and liberal lobbies.

“They were throwing bombs because the Democratic Party was being run by unalloyed liberals who were completely in the thrall of old-line interest groups,” a White House aide under Mr. Clinton, Matthew Bennett, said. In the 1992 campaign, the formula was adopted by an Arkansas governor, Mr. Clinton, who saw the DLC as a way to set himself apart from other contenders for the presidential nomination.

To an extent, the council is a victim of its own success.The group’s talk of fiscal responsibility, while rare in Democratic circles two decades ago, is now commonplace even among the party’s most liberal officeholders. Another polarizing issue the DLC championed in the 1990s, welfare reform, no longer causes much consternation among Democrats.

However, two centerpieces of the council’s agenda, a “muscular” foreign policy and support for free-flowing international trade, are squarely in conflict with positions many political analysts believe could carry the Democrats to victory this fall and beyond. Most Democratic lawmakers who backed President Bush’s invasion of Iraq have been steadily retreating from their support. A longtime DLC leader who has been unwavering in his support for the war, Senator Lieberman of Connecticut, is facing a strong primary challenge from a candidate close to the netroots, Edward Lamont. A poll released yesterday showed the challenger with a slight lead.

Mr. Reed said Mr. Lieberman’s primary fight should not be seen as a referendum on the DLC, in part because “diehards” are more likely to turn out for a mid-summer election. “He’s a great Democrat and a good friend, and we think he’ll win,” Mr. Reed said.

“On the war, I don’t think there’s a clear winning position,” the former White House aide said. “Republicans think that’s their best issue. I don’t think it’s a good issue for anybody.”

Mr. Sirota, who recently wrote a book attacking the influence of moneyed interests in politics, “Hostile Takeover,” said the trade issue is a powerful one and the DLC’s stance has muddled the party’s message. “That has been in part responsible for Democrats losing blue collar, middle-America and losing election after election,” he said.

Mr. Sirota scoffed at the notion that, with Mrs. Clinton’s prodding, the DLC can lead a “big tent” coalition. “You can’t put the steelworkers, working class people, in the same tent with an organization that continues to push trade policies that sell out workers,” he said. “I don’t care how big a tent you have. You just can’t do it.”

Absent from this year’s speaking schedule is a former Virginia governor, Mark Warner. An aide said Mr. Warner, who spoke at last year’s conference and is aligned with many of the DLC’s policies, is on a “longstanding vacation.” He has also been aggressively courting online activists and may see little political upside in highlighting his ties to the centrist group.

The bloggers’ distaste for the DLC is not strictly ideological. “I tend to think it’s as much about elitism as about political philosophy,” a professor at the University of Virginia, Larry Sabato, said. “They view the DLC as a bunch of insiders from Georgetown who try to control the party and it’s nomination.

The Web activists’ struggle is a mirror image in many ways of the DLC’s challenge to party orthodoxies two decades ago, a Democratic strategist, Kenneth Baer, said. “

“They would have been the DLC, when the DLC was founded,”Mr.Baer, co-editor of a new quarterly, “Democracy: A Journal of Ideas” said. “Their criticism that Washington insiders are calling the shots, it’s exactly the DLC’s critique,” he said.