Paul Ryan is arguably the first member of Generation X to join a presidential ticket, and he represents many of the cultural and political hallmarks of his era. He listens to Rage Against the Machine, is a workout fanatic — and is deeply skeptical that entitlement programs designed to help older Americans will be solvent by the time he qualifies to receive them two decades from now.

What remains unclear is how many of the more than 70 million Americans in his generational cohort Ryan, born in 1970, can move to the Republican side of the ballot. Although younger voters have expressed enthusiasm for the vice-presidential pick — giving Mitt Romney a needed boost among a demographic that has tended toward President Obama — it is less certain that they will be enthusiastic about the ideas for restructuring government programs such as Medicare that have come to define Ryan.

Polling in recent years suggests that people under age 50 do not think they will be able to depend on Medicare’s health-care benefits or income from Social Security once they retire. An August 2010 CNN poll found that 70 percent of respondents under 50 do not believe they will see benefits from Social Security, while 61 percent of respondents age 40 through 49 in a June 2011 Pew Research survey said Medicare needed either major changes or a complete overhaul.

The question is whether the shared cultural bond that came from listening to grunge and watching “Friends” can translate into a political connection. So far, Ryan, a policy wonk with three children, has not emerged as a cultural icon for his generation — certainly not in the way that Barack Obama or Bill Clinton did when they took the national spotlight.

There is no consensus definition of Generation X, but it comprises the post-baby boom generation, born roughly between the mid-1960s and early-1980s. As such, Ryan is the first clear-cut, indisputable member of this demographic to run on a presidential ticket. Barack Obama and Sarah Palin could qualify, but they fall into a gray area — born in 1961 and 1964, respectively — that could just as easily place them in the boomer category.

Neil Howe, a demographer and co-author of the book “Generations,” says Gen X voters might be willing to embrace tough cuts for the sake of sustainability, especially because of their characteristic self-reliance. “They’re relatively more likely to say these benefit programs won’t survive, and we ought to take a chance doing something with reform,” he said. “Taking it on the chin a little in order to create a more secure future for their children, I think, is something that would resonate with them.”

Howe said Gen Xers grew up somewhat neglected, with relatively self-centered parents who didn’t think the world revolved around children — the opposite of today’s helicopter parents. “These were hurried kids given self-help guides and taught to rely on themselves,” he said.

Todd McDonald, a 44-year-old venture capitalist and independent voter from Ashburn, said he is warm to Ryan, but he opposes Medicare vouchers and Ryan’s resistance to defense cuts that could complement possible reductions in discretionary spending. “I like Ryan as a person — he seems like a good family man,” McDonald said. “But I don’t agree with his views.”

In recent interviews, Gen X voters across the ideological spectrum expressed interest in Ryan, who remains a relative unknown, with some saying they were intrigued by having one of their peers on a national ballot for the first time.

“I’m not a Romney fan, but I like the fact that he picked a young candidate,” said Mark Quandrini, a 38-year-old lab technician from Centreville. “I just think we need an infusion of youth and a younger perspective, whether it’s Democrats or Republicans. The older generation has lost its way.”

Brett Cooper, a registered Republican from Raleigh, N.C., said he is undecided about how he will vote, and though he sees Ryan’s youth as a plus, it will not matter as much as his policies.

“I don’t think Romney’s stupid for selecting Ryan, particularly because of the whole Gen X thing,” said Cooper, a 43-year-old tech-sector salesman. “But it’s his record that’s important for me.”

Cooper said he does not find fault with the way Obama handled the stimulus program and believes tax hikes might be necessary to balance the federal budget even though it could hurt job growth. Yet Cooper also agrees with Ryan about the need for tough cuts.

“There’s not going to be enough money for Medicare with us,” he said of Gen Xers. “That’s one thing I think he’s trying to address, but it’s going to be the specifics that matter to me.”

Dan Hill, 43, a libertarian from Reston who owns a public-relations firm, said it is not important that someone his age is running for office. “That really doesn’t move me,” he said. “I’m more about credentials, ideas, beliefs. He seems like a thoughtful person willing to put ideas on the table.”

Hill sees Ryan’s budget proposal as part of a debate that’s necessary to get the federal government’s financial house in order. “We’re in bad shape,” he said. “We need to find a way to solve our budget problems, and I just don’t see how we can do that without looking at the big programs we spend money on.”

Even some Republicans who favor Ryan are skeptical about his political effectiveness. Mike Pratt, a 35-year-old registered Republican from Sterling who works in IT support, said he sees Romney’s pick as a gimmick. “I think he chose Paul Ryan based on the fact that he [Romney] is not doing very well,” he said. “Do I think it’s going to work? No. I think Obama’s going to win a second term.”

Pratt said he has decided to vote for Romney.

On the other side of the political spectrum, some Democrats said the Ryan pick puts Romney at a disadvantage — one that the congressman’s youthfulness can’t overcome. “Choosing Ryan makes it that much harder for people to relate to Romney,” said Kim Sauvageot, 40, of Minneapolis. “With his policies, people won’t think he’s for pulling for them.”

At the younger end of the Gen X spectrum, Bryan Watts, a 32-year-old from Herndon who is vice president of a home-remodeling company, said he is leaning toward voting for Romney because he believes Ryan’s age makes him better prepared to tackle today’s problems. “I think he can relate more to what people in my age bracket are worried about,” he said.

Watts said he’s tired of the gridlocked American government and wants a president who succeeds with bold initiatives, regardless of the obstacles. He talked yearningly about how Ronald Reagan took on the Soviet Union and Bill Clinton balanced the federal budget.

“If we could make a prototype of those two presidents, that would be great,” Watts said. “I want a solid leader now — someone who gives us faith and makes us feel like our country is on the up.”