Young people always have been the core workers in presidential campaigns, but seldom have they been so inspired by a candidate or so effectively molded into viral campaigners and voters as they were in this election cycle.

Their involvement was one of the linchpins of Barack Obama's victory. Data released yesterday showed that young people cast 2.2 million more votes in this presidential election than in 2004, and the vast majority of those votes were for Mr. Obama.

Still, those numbers don't tell the whole story.

Although more young people voted, so did more older ones. In the end, people under 30 made up 18 percent of the electorate.

That's up a percentage point from the last presidential election. But political scientists say the impact of young people could be even more significant because their votes were weighted more heavily toward Mr. Obama.

"I don't know if they swung the election, but they certainly made a difference. There's such a huge proportion of them that turned out for Obama," said Joan Mandle, executive director of Democracy Matters, a nonpartisan group that promotes political involvement of young people through 80 chapters at college campuses nationwide.

It's doubtful, she said, that young voters have ever had so much influence on a presidential election. They voted in a 66-32 split for Mr. Obama, compared with 52-46 among all voters.

In State College in Centre County -- one of the largest college towns in Pennsylvania -- about seven out of 10 voters cast ballots for Mr. Obama.

Other college towns also turned out the vote for Mr. Obama. In Monroe County, Ind., home to the University of Indiana, Mr. Obama won 66 percent of the vote to Mr. McCain's 33 percent.

Political scientists and strategists say the reputation of outgoing President Bush accounts for some of the difference between voting patterns of younger and older voters.

According to a Temple University poll, while voters of all ages give similarly low approval ratings to Mr. Bush, only older voters have memories that extend beyond his presidency.

"Older voters still see the Republican Party as the party of Ronald Reagan," said Republican pollster and strategist David E. Johnson, chief executive officer of Strategic Vision.

"The only Republican leader younger voters know is George W. Bush, and they view his presidency as flawed."

Voters like 23-year-old James O. Allan of Allison Park say they're not jaded. Instead, they felt inspired by a candidate for the first time.

"My generation never really had a JFK or a Martin Luther King. Obama became our first guy that, when you hear him speak, it has the same kind of effect those people had," he said.

"People were much less excited four years ago than they are now. With [John] Kerry and Bush, we were voting for the lesser of two evils. Nobody was able to inspire young people like Barack Obama did this year," he said. "He was a rock star before the primaries were over. You'd see his campaign signs in places you wouldn't expect to see them."

One such place, he said, was Colorado Springs, a conservative military town an hour from Denver, where Mr. Allan recently graduated from the University of Colorado .

"It's a place that previously Democrats would have written off, but there's this young and energetic candidate who is willing to go there and campaign because he wants to represent everybody," Mr. Allan said.

Political scientists and strategists say the Obama campaign was successful because of its willingness to visit all areas of the country, even such Republican strongholds as Pennsylvania's Lancaster County.

"It wasn't about 'us versus them' thinking, but [a message] about how people in every walk of life can band together and create positive change in the world," said Hanna McIntosh, 20, a Lancaster native who now attends Chatham University and is a leader in its Students for Barack Obama chapter.

The campaign also combined tried-and-true door-to-door grass-roots efforts with an extraordinary use of new technology, including social networking Internet sites that kept the tech-savvy younger generation interested and involved during a lengthy two-year campaign.

Reviewing and swapping candidate-related information on blogs, Facebook or elsewhere online also encouraged a "hive mind" for some students who were determined to stay as informed and involved as their peers, said Lissa Geiger, 21, president of the University of Pittsburgh chapter of the Pennsylvania Federation of College Democrats.

"The Internet really changed things for young voters this time around," said Joan Hanna, 19, of Indiana, Pa., a sophomore at Chatham University and another leader of its Students for Barack Obama chapter.

"Obama's use of the Internet [enabling students] to donate money or take advantage of volunteering opportunities -- it was just a lot easier than having to go to a place and sign up," she said. "It had a huge impact on the race."

Voters weren't just seeing messages on TV in this election cycle, but were receiving text messages, forwarding e-mail messages, viewing online videos and interacting with one another on Web forums.

"It was more than just Obama's campaign having a strong presence online. It was Obama supporters making their mark online as well," said Michal Ann Strahilevitz , associate professor of marketing at Golden Gate University in San Francisco.

"Inspiring the youth vote was as much about how the message was delivered as about the strength and inspiration of the message itself."

Mrs. Mandle said young voters were drawn to Mr. Obama's energy, his promise to help make college more affordable and his levelheaded response to economic problems like the recent financial bailout package approved by Congress.

"Young people wanted to give this youngish, articulate, charismatic candidate a chance, and I think that's something we all wanted," she said. "People will vote if they're excited. This idea that people are apathetic is baloney. When people don't vote it's because they don't think they have political candidates they can believe in."

When a candidate they believe in wins, the result can be the kind of euphoria that drove more than 1,000 young people into the streets of Oakland to chant, embrace and weep with one another yesterday morning.

"All these people were hugging and dancing, and they were so happy and joyful," said Ms. McIntosh, who left her house in Shadyside to join the throng on Forbes Avenue on the Pitt campus. "It was a massive celebration and it was very emotional and powerful."