Ah, the enduring American Dream. The idea that anyone who works hard enough can climb the ladder and achieve success: a lovely home in the suburbs, luxury cars in the garage, the kids off to a good college and the retirement in a sunny locale.
The reality is more complicated.
Although the economy is slowly improving, experts say the deep recession and weak recovery may have exacerbated decades-long trends that were already making it tough for Americans to move up the ladder and, perhaps, achieve the American Dream.
The incredibly weak job market of the past five years, in particular, may mean that more people feel that they are doing everything right—working hard, going to college, following the rules—and still aren't getting ahead.
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"If there aren't enough jobs in general, then we have a systemic problem that threatens the American Dream," said Steven Fazzari, an economics professor at Washington University in St. Louis, who recently taught a course on the economic realities of the American Dream.
Americans also are known for their resilience, and Pew Charitable Trusts' data have shown that about two-thirds believe they have achieved or will achieve the American Dream. But a separate Gallup poll from last year found that only about half of Americans are satisfied with the opportunity for a poor person to get ahead by working hard.
Mary Conti is not one of them.
Conti, 42, was the first person in her family to go to college, and at first that degree seemed to be a springboard into a middle-class life. Conti was laid off from her job as a reporting analyst about a year ago, and she and her husband have fallen badly behind on their bills.
A year after Conti was profiled by NBC News for a story on those who fear falling through the economic cracks, she said her experience has left her feeling that it also takes good fortune to climb the ladder.
"I think it's still possible, I guess," Conti said. "It's not as much hard work, I think, as it used to be. It's hard work, but it's also luck."
The reality is that, even in good times, it is difficult and rare for Americans born very poor to become wealthy.
"In the United States, people who are coming from low-income families are highly likely to be low-income themselves," said Erin Currier, director of the Pew Charitable Trusts' Economic Mobility Project. "That sort of rags-to-riches story … is very unlikely."
That may come as a surprise to many people who feel like they are doing better financially than their parents.
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Mary C. Daly, senior vice president with the Federal Reserve Bank of San Francisco, said her research showed that about two-thirds of adults have higher family incomes than their parents after adjusting for inflation.
But those increases have come with an improvement in our standard of living, and very few people are doing so much better that they can move up.
"If you want to think about going up and down the economic ladder, you just don't see it," Daly said.
Overall, about one-third of the households that Currier studied could be classified as upwardly mobile—meaning that they had higher household income and were at a higher point on the income distribution chart than their parents.
The Pew researchers also found that just 4 percent of people who grew up in a household at the bottom fifth of the income ladder made it to the top fifth as adults.
Fazzari said the American Dream may have been most validated in the period after World War II, but most people have been struggling with stagnating wages since at least the 1980s.
The gap between rich and poor has widened in the past couple of decades as compensation for the nation's wealthiest workers has grown substantially faster than for everyone else.
For many people, things have likely gotten even tougher recently, as they deal with the triple whammy of the housing bust, financial crisis and high unemployment. The nation's median household income in 2011 was nearly 9 percent lower than in 1999, after adjusting for inflation.
The shocks associated with the recession, such as a stint of unemployment, can be especially devastating to a low-income household's long-term prospects, according to Pew's Currier.
To pay rent and buy food when there's no steady paycheck, some people with fewer resources are forced to drain the savings accounts intended to pay for college or retirement, she said. Others may turn to devices such as payday loans, taking on costly debt.
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"It actually can really derail what were otherwise families that had a bit of a foothold on the middle class," Currier said.
Heather Wyatt-Nichol, director of the Masters in Public Administration program at the University of Baltimore, said her research has shown that even when some of the nation's poorest people are able to ascend, they sometimes end up falling back down a few years later.
Perhaps people need to rethink the definition of the American Dream, putting less emphasis on having a huge house and lots of things and more on building successful communities, she said.
"We all want to be able to support ourselves and our family, and have a decent standard of living," Wyatt-Nichol said. "But in many ways, I think we need to scale back what the American dream means to us."
—By CNBC's Allison Linn. Follow her on Twitter @allisondlinn or send her an e-mail.