Dean's rise to party chair bolsters ties to activist networks on the left.
Faced with the challenge of transforming themselves from a minority to majority party, Democrats are increasingly showing more defiance than doubt - and are now moving aggressively to challenge President Bush's agenda, with the party's public face becoming more dominated, for now, by figures on the left.
This weekend, Democrats are poised to elect as their party chairman former Vermont Gov. Howard Dean, whose full-throated opposition to Mr. Bush's policies - particularly the Iraq war - shot him to the top of the presidential primary heap before his candidacy flamed out with the now-infamous scream.
Dr. Dean will join a chorus of aggressive Bush critics - from Sen. Barbara Boxer of California to Sen. Edward Kennedy of Massachusetts - who lately have grabbed the spotlight while the overall party faces something of a leadership vacuum, with no presidential nominee to set the tone.
Strategists say Dean's reemergence does not necessarily point to an ideological repositioning of the party as a whole. For one thing, the former governor has said he'll take his cues on policy and message from the congressional leadership, and his supporters say he may present a more moderate face than the image that emerged during his primary campaign.
At the same time, other prominent Democrats, such as Sen. Hillary Rodham Clinton of New York, have made noticeable shifts toward the center of late, softening their rhetoric, if not position, on issues such as abortion.
But Dean's ascent, despite uneasiness among some in his party, does indicate the extent to which Democrats are finding themselves defined - and even united - by the demands of opposition.
Although Democrats may still face fissures over issues such as the Iraq war, and how better to appeal to mainstream American values, they are more immediately engaged in major battles with the Bush administration over issues such as Social Security - and may not have the luxury of internecine fighting over the direction of the party.