William Kistler views retirement like someone tied to the tracks and watching a train coming. It's looming and threatening, but there's little he can do.
Kistler, a 63-year-old resident of Golden, Colorado, has been unable to build up a nest egg for himself and his wife with his modest salary at a nonprofit. He has saved little in a 401(k) over the past decade, after spending most of his working life self-employed. That puts him far behind many wealthier Americans approaching retirement.
"There is not enough to retire with," he said. "It's completely frightening, to tell you the truth. And I, like a lot of people, try not to think about it too much, which is actually a problem."
With traditional pensions becoming rarer in the private sector, and lower-paid workers less likely to have access to an employer-provided retirement plan, there is a growing gulf in the retirement savings of the wealthy and people with lower incomes. That, experts say, could exacerbate an already widening wealth gap across America, as more than 70 million baby boomers head into retirement - many of them with skimpy reserves.
Because retirement savings are ever more closely tied to income, the widening gulf between the rich and those with less promises to continue - and perhaps worsen - after workers reach retirement age. That is likely to put pressure on government services and lead even more Americans to work well into what is supposed to be their golden years.
Increasingly, financial security for retirees reflects how much they have accumulated during their working career - things like 401(k) accounts, other savings and home equity.
Highly educated, dual income couples tend to do better under this system. The future looks bleaker for people with less education, lower incomes or health issues, as well as for single parents, said Karen Smith, a senior fellow at the Urban Institute, a Washington think tank.
"We do find rising inequality," said Smith, who added that it's a problem if those at the top are seeing disproportionate gains from economic growth.
Incomes for the highest-earning 1 percent of Americans soared 31 percent from 2009 through 2012, after adjusting for inflation, according to data compiled by Emmanuel Saez, an economist at University of California, Berkeley. For everyone else, it inched up an average of 0.4 percent.
Researchers at the liberal Economic Policy Institute say households in the top fifth of income saw median retirement savings increase from $45,539 in 1989 to $160,000 in 2010 in inflation-adjusted dollars. For households in the bottom fifth, median retirement savings were down from $8,433 in 1989 to $8,000 in 2010, adjusted for inflation. The calculations did not include households without retirement savings.
Employment Benefit Research Institute research director Jack VanDerhei found that in households where annual income is less than $25,000, nine in 10 saved less than $10,000, up slightly from 2009. For households with six-figure incomes, 42 percent saved at least $250,000, up from 34 percent five years earlier.
The days of retirees being able to count on set monthly payments from pensions continue to fade among non-government workers. Only 13 percent of private-sector workers now participate in "defined benefit" plans, compared with a third of such workers in 1985. They've been eclipsed by "defined contribution" plans, often 401(k)s, in which employers match a portion of employee contributions.
Americans know they need to save for retirement. The trick for many is actually doing it. It's estimated that about half of private-sector workers don't take part in a retirement plan at their current job.
"Over the years, all I've been able to do, especially as a single parent, is just pay your bills every month," said Susan McNamara, a 62-year-old adjunct professor from the Boston area. "Anything that's left over is used up when your car breaks down or when the furnace breaks down. ... There's never anything left over, ever."
McNamara is divorced and her son is now grown. But she has had heart issues linked to cancer in 2004 and related financial worries. She sold her home to meet expenses. McNamara has a defined contribution plan from past stints as a full-time professor, but its balance is under $50,000.
Or consider Kistler, who makes $41,000 a year working as a benefits counselor for a nonprofit health care provider. He has no substantial savings beyond the 401(k) worth roughly $19,000, and he has debt. He plans to keep working.
Kistler is philosophical about being on the short end of a retirement gap, though he wonders what will happen when boomers in his financial situation begin retiring by the millions.
"This next 10 to 15 years is going to be quite interesting," he said.
EBRI, a Washington-based nonpartisan research group, projects that more than 55 percent of baby boomers and the generation that follows them, Generation X, will have enough money to last through retirement.
But EBRI also found the least wealthy boomer and Gen X households are far more likely to run short of money in retirement. Under some models, 43 percent of those in the lowest quarter run short of money in the first year of retirement.
VanDerhei, EBRI's research director, said members of that group are relying mostly on Social Security and lacked consistent access to retirement plans over their careers.
Many of those retirees will find that it won't be enough, David John of AARP's Public Policy Institute said, noting the average monthly Social Security retiree benefit last year was about $1,300.
"In the long run, if we have significant numbers of people retiring on Social Security and very little else, there's going to be a tremendous pressure on state and local governments for additional services, ranging from health to housing to libraries," John said. "There's going to be significant pressure on the national government to provide additional support."
John said a good first step would be to ensure more workers have the ability to save through employer-sponsored retirement plans.
For many, it will mean working to a later age and cutting back.
In Brooklyn, 60-year-old Madeline Smith is already thinking about a modest future. While she has no illusions about living the "little fairy tale" of a cushy retirement, she also is confident she can get by, maybe working part-time, living simply or even renting out her house.
"Sometimes you have to learn to be a little bit more conservative," she said. "I think a lot of people are learning that now as they get older."