The number of people who believe they could be born poor, work hard and get rich is at a two-decade low in New York Times polling, further evidence of the fade of the long-held idea of the American Dream.

Less than two-thirds of respondents (64 percent) said that scenario was possible while 33 percent said it was not.  Over the past decade of the Times asking the question, the number of people who believe you can start off poor and get rich has steadily declined. In March 2005  80 percent said it was possible. By October 2011 it was at 75 percent and dropped to 71 percent in July 2012.  The latest dip into the mid 60s marks only the second time the number has been that low since the Times has been asking the question. The other time? In January 1983, when just 57 percent of people said being born poor and becoming rich through hard work was possible.

That 1983 low is worth exploring. It came right in the teeth of a deep economic recession; unemployment nationwide was over 10 percent and had reached the high teens or even low 20s in some states. In Ronald Reagan's 1983 State of the Union address, he began this way: "As we gather here tonight, the state of our Union is strong, but our economy is troubled. For too many of our fellow citizens-farmers, steel and auto workers, lumbermen, black teenagers, working mothers -- this is a painful period."

Of course, 1983 was also a turn-around year for the economy. By year's end, the unemployment rate had dropped almost two points and Reagan's reelection a year later went from questionable to certain. (Unfortunately, the Times didn't ask the "start poor, get rich" question again until the mid 1990s, so we have no way of knowing whether it improved along with the economy.)

It's easy to believe there is direct correlation between people not believing in the American Dream and prolonged periods of economic struggle.  Which would explain the downward trend of the numbers in the Times poll over the last decade as the economy has sputtered. The question is whether the slowness of the current recovery is what's to blame for the extended pessimism about hard work achieving results or whether we, as a country, have simply entered a different stage in our relationship with the idea of the American Dream.

There's some reason to believe the latter explanation is more correct.

Consider this, from the 2014 national exit poll: Almost half of all Americans — 48 percent — said they expected life for "future generations" to be "worse than life today," while 22 percent said it would be better. Another 27 percent said life would be about the same. Do the math and you see that more than twice as many people are pessimistic about the future that they will leave their kids as those who are optimistic.

Or this, from a CNN/ORC poll in June: Just one in three people believe "most children in this country will grow up to be better off" than their parents; 63 percent said their kids will be worse off.

Now, a few caveats:

1. Asking people whether they can be born poor and get rich through hard work is not, for everyone, a definition of the American Dream. "Rich" and "successful" are not synonymous. So there may well be people who believe you can be born to humble circumstances and achieve success who don't buy into the poor/rich dynamic presented in the Times poll.

2. Comparing people who say they believe you can be born poor and get rich to people who say things either will or won't be better for future generations isn't apples to apples.

Those caveats aside, though, there does seem to be a dip in the twin ideas that a) the country is moving, inexorably, in a better direction and b) the opportunity to succeed exists for all of us (mostly) equally. That presents a major challenge for politicians who have spent the last two decades leaning heavily on what now looks like a somewhat outdated idea of not only the American Dream but whether it can be achieved.