John F. Kerry's victory in the Virginia presidential primary yesterday was both deep and broad, as the Massachusetts senator won by significant margins in virtually all of the key Democratic constituencies, even capturing rural and "southern" regions that had been viewed as tilting to his challengers.

In the rural western and southwestern areas of the state, which were considered prime territory for his closest competition, Sen. John Edwards (N.C.) and retired Army Gen. Wesley K. Clark, Kerry won roughly 50 percent of the vote, according to exit polls. Among African Americans, who made up about a third of voters, Kerry won 61 percent; among military veteran households, to whom Kerry appealed with ads about his Vietnam service, he won 53 percent.

"He's clearly answered his critics who said he couldn't win in the South," said Steve Jarding, the 2001 campaign manager for Gov. Mark R. Warner (D) and a fellow at the Institute of Politics at Harvard University. "Momentum carried him through."

In Northern Virginia, in Arlington, Fairfax, Loudoun and Prince William counties and the city of Alexandria, Kerry received 54 percent of the vote. Former Vermont governor Howard Dean made his best showing in the region, with 11 percent of the vote, and Edwards garnered 21 percent. Clark received 10 percent.

Kerry piled up enormous margins among voters who prefer a seasoned leader who can win.

He was supported by 76 percent of voters who want a candidate who can beat President Bush and 66 percent of voters who want a candidate with the "right experience."

"From the Democratic point of view, we want the field of candidates narrowed as quickly as possible so that we can have a viable candidate in November," said Pat Kearns, 58, a Fairfax voter who runs a nonprofit group, explaining her vote for Kerry.

Patricia Coan of Fairfax, a retired medical practice manager, said: "I voted for Kerry for the same reason most Democrats are voting for him -- he can beat George Bush. I like Edwards very much, but I think his lack of experience would hurt him in the general election."

Like many other Democrats, she said she'd like to see a Kerry-Edwards ticket.

Edwards won more support among voters who want a candidate with "a positive message" and "the right temperament." He drew even with Kerry among those who want a candidate who "cares about people like me."

To win in Virginia, the candidates had to appeal to the state's varied Democrats, campaign strategists said: African Americans, who supported Jesse L. Jackson in 1988, the last time a Democratic presidential primary was held in the state; the high-income, highly educated and generally liberal Democrats in Northern Virginia and some other suburbs, who tilted toward Michael S. Dukakis that year; and finally, the more conservative Democrats in Southside and southwestern Virginia, many of whom voted for then-Sen. Al Gore of Tennessee, whom they considered a conservative.

Kerry won among every group but conservatives, with whom he ran even with Edwards, according to an exit poll conducted for the National Election Pool by Edison Media Research and Mitofsky International.

"These are awful margins," said Larry Sabato, a political scientist at the University of Virginia. "It's almost 2 to 1. The southern candidate argument isn't working for Edwards, and neither is the rural appeal."

Although the victory was large, its significance for Democrats in a fall presidential campaign was unclear. No Democratic presidential nominee has won Virginia since Lyndon B. Johnson in 1964. In 2000, George W. Bush beat Gore by 53 percent to 44 percent.

The voters in yesterday's primary came from a slice of the Virginia electorate that is more liberal than Virginia Democrats generally.

More than 40 percent of voters identified themselves as liberal, compared with 34 percent of Virginians voting for Gore in the 2000 presidential election. More than 70 percent of yesterday's voters disapproved of the decision to go to war with Iraq.

Kerry won 52 percent support among liberal voters but 38 percent among conservative voters.

Turnout was light. More than 370,000 people voted, barely eclipsing the 1988 total, when about 365,000 voted.

Many of the voters may have selected Kerry because he racked up wins elsewhere and was considered more electable, rather than because of his specific appeal to Virginians.

More than 40 percent of voters made their decision in the last week, when front-runners were making whirlwind tours of the state. More than 1 in 4 named beating President Bush as the most important quality in a candidate.

Jarding said: "I don't say this to belittle [Kerry's] campaign or his message, but there's no question that Virginia didn't get a chance to know these candidates well, so they took their cues from more intangible indicators such as what other states did and endorsements."

Former congressman L.F. Payne, chairman of the Clark campaign in Virginia, agreed that the momentum Kerry gained earlier in other states was difficult to overcome during the short, intense campaign in Virginia.

"Both Edwards and Wes Clark spent a fair amount of time in Southside and southwest Virginia," Payne said. "But people are very affected by what they were seeing in the national media, and the story since Iowa had been that John Kerry was leading the pack and running away with it."

Mary A. "Mame" Reiley, a Democratic Party activist in Virginia, disputed the idea that Kerry won the election with momentum rather than an appeal that crosses regional lines. She said that Virginians had studied their choices carefully and that Kerry's victory proved his appeal in a diverse state.

The support of African American voters was considered one of the biggest electoral prizes in the campaign. African Americans made up 33 percent of voters yesterday, according to exit polls.

Rep. Robert C. "Bobby" Scott (D-Va.), an African American who is a Dean supporter, said Kerry, Edwards, Clark and Dean were "very active in making a strong pitch to the African American community."

New York activist Al Sharpton captured 9 percent of African American votes, exit polls showed.

Kerry earned some highly sought-after endorsements from African American leaders such as state Sen. Henry L. Marsh III (D-Richmond).

Like many voters yesterday, Teresa Jones, 44, a pharmacist's assistant from the Richmond area who is African American, said she began to look at Kerry closely after the holidays. Initially, she said, she was leaning toward Clark and Dean, but as she focused more on the race, she liked Kerry's senatorial experience and his stances on the war.

She said she was not concerned about the fact that he is from the North. "I know a lot of people say a southerner won't vote for a northerner, but we've got to get over that as a party. We need to get those Republicans out," Jones said.

Staff writers Steven Ginsberg, Chris L. Jenkins and Richard Morin contributed to this report.

A woman walks past John Edwards supporters on her way to vote in Arlington. Edwards received 21 percent of the vote in Northern Virginia.