“I particularly like his foreign policy point of view,’’ Habeshian said. “We have been sticking our noses into other countries’ business for years and it’s come back to bite us on the rear.’’ He said he is “not completely sold’’ on Paul’s economic policies, which call for a $1 trillion federal budget cut in the first year, the elimination of five Cabinet-level departments, and the end of the federal government as we know it in a range of regulatory and entitlement programs.

With him were two high school classmates from Barnstable, Kayla Kalweit, a student at Suffolk University, and Riley Tamash, a student at Westfield State University, and a classmate from Clark, Garin Habeshian of Waltham. All said they are disillusioned with the state of the country and looking to Paul, the preacher of an extreme laissez-faire form of economics and a non-interventionist foreign policy that many critics consider isolationist.

“Three years of crap,’’ said Riley. He doesn’t agree with every policy of Paul, the libertarian-leaning constitutionalist, Riley said. “But I agree with a lot of what he says, especially on the economy and foreign policy. I agree with him when he says that we shouldn’t be the policeman of the world.’’

James Riley, a 20-year-old from Barnstable attending Clark University, is a registered Democrat who was enthusiastic about Obama four years ago, though he was too young to vote for him. Yesterday, he and three friends drove to Nashua to attend the Paul rally.

For a generation that has lived with costly wars for a decade, a sluggish economy for as long as they can recall, and a $15 trillion national debt that threatens their future, Obama is no longer the first political option for many voters in their 20s.

Young voters were a major force in Barack Obama’s campaign to win the Democratic nomination and the White House in 2008. With polls showing declining enthusiasm for the president in that voting bloc, Paul has become a magnet for disaffected young men and women who want change, albeit of a kind radically different from that promised by Obama four years ago.

The phenomenon is national, not limited to the Midwest. It was in evidence yesterday at Nashua Airport, where the “Ron Paul’’ chants started before the candidate even arrived for a huge, raucous rally in a packed general aviation hangar.

Perhaps the most striking statistic to come out of the Iowa caucuses, where Paul finished a close third, was entrance poll data showing that the 76-year-old Texas congressman captured 48 percent of the vote among those under the age of 30 in a six-candidate field.

NASHUA - As he touched down in New Hampshire yesterday to campaign before Tuesday’s Republican presidential primary, Ron Paul was greeted by what has become a familiar sight - a large, enthusiastic crowd, about half of them younger voters.

If there is a common theme to young voters’ complaints - and why Paul appeals to them - it is frustration about a dysfunctional political system and anxiety about a future with limited employment prospects or the likelihood of living a better life than their parents lived.

“Ron Paul talks about the whole system being broken, that it needs to be changed,’’ said Wayne Lesperance, a professor of political science at New England College. “I think that resonates with them. They have a healthy dose of cynicism because they believe the system is broken on a lot of levels.’’

Younger voters have no allegiance to a particular party, said Lesperance, the codirector of College Convention 2012 in Concord, attended this week by college and high school students as well as some of the presidential candidates or their surrogates. Paul was not among them because of a schedule change.

One conventioneer, Tyne Uzo, a 20-year-old from Wading River, N.Y., and a student at Rhode Island College, said that while she personally doesn’t support Paul’s candidacy, or that of any other presidential candidate, she has many friends who do.

“I originally thought it was because he wants to decriminalize marijuana, but that’s not it; it’s about ending the wars and ending the Fed,’’ she said, referring to Paul’s call to eliminate the Federal Reserve and its ability to increase the supply of money. “They learn about it through Ron Paul. It’s the gateway to constitutional values and libertarianism.’’

At Paul’s New Hampshire headquarters on the outskirts of Concord, a roomful of 20-somethings were busy making calls to voters over sophisticated voice-over-Internet phones that allow them to punch coded voter identification information into a campaign databank. All 25 stations were full at 11 a.m.

Among those at the headquarters were volunteers who have traveled thousands of miles, first to Iowa and now to New Hampshire to help the Paul campaign.

One is Sarah Franklin, a 22-year-old from Seattle who is studying English literature at the University of Washington. Raised in a family of Democrats, she said this is her first involvement in politics. “I don’t affiliate myself with the Republican Party,’’ she said. “I affiliate with the voice of freedom.’’

“Ron Paul represents an idea, the idea of freedom and individual liberty,’’ she said. “If I’m going through airport security, I can’t make a joke about the [Transportation Security Administration] or they have the right to arrest me,’’ Franklin said. “That’s a problem.’’

Franklin has spent two weeks of her semester break volunteering for Paul and is considering extending it so she can go on to South Carolina, site of the second primary on Jan. 21. Like all these out-of-state volunteers, she is paying for her own transportation costs.

So is Timothy Shanks, a 22-year-old from South Texas studying for his doctorate in mathematics at Texas A&M University. The product of a conservative family, Shanks also volunteered to work on Paul’s campaign in Iowa before heading to New England.

“What Ron Paul stands for is close to what the Republican Party once stood for for many decades,’’ Shanks said. “That’s small government, limited government, and a sound economy, and sound money is an integral part of that.’’ Shanks said he is alarmed by the size of the national debt and its rate of growth. “This is not sustainable,’’ he said.

Many young people see Paul as authentic, honestly believing what he says and not shifting his views based on the prevailing winds. “That’s a huge draw, his integrity,’’ Shanks said.

Brian C. Mooney can be reached at brian.mooney@globe.com.

© Copyright 2012 Globe Newspaper Company.