​The secrets of America's "supersavers"

While most Americans struggle from paycheck to paycheck, a few rare birds are able to sock away million-dollar retirement accounts on middle-class incomes.

While not everyone may be able to put aside as much as these dedicated investors, their accomplishments offer some valuable lessons. Literally trillions are at stake, given that the U.S. retirement deficit has been estimated as high as $14 trillion.

Some habits of the supersavers may not seem surprising because they're the kind of nuts-and-bolts financial advice that's familiar to many Americans. But other traits may be less understood, such as learning from past mistakes and seeking out better financial advice.

As detailed by The New York Times, Chris Reining, who was earning $75,000 several years ago, made a goal of reaching a goal of saving $1 million by the time he turned 35. He told The Times he now has $1.2 million in savings.

"I didn't win the lottery, I didn't inherit any money, and I didn't start a company," Reining wrote on his blog about his achievement. "If you're in the same situation then the fastest way to $1 million is to decrease spending and increase income. Those are the two levers you have control of."

To be sure, that advice may apply mainly to educated, white-collar workers with retirement plans and middle-class incomes. Americans who lack employment skills or a college degree and are struggling to make ends meet in low-paying jobs may find such advice hard to swallow.

Earning more money certainly helps when it comes to building a larger nest egg. Millennials who qualify as "supersavers" earn about $73,000 annually, compared with the average of $46,000 per year for those who don't meet the cut, according to a recent Fidelity Investments study. Putting aside more money may simply be easier if you have a little extra gravy to dip into.

That same pattern held for Generation X professionals. In that group, supersavers enjoy average salaries of $108,900, compared with $68,900 for Gen Xers who weren't saving as much.

By Fidelity's calculations, millennial supersavers devote 11 percent of their salaries to their retirement accounts, while their company match provides another 4 percent, giving them a savings rate of at least 15 percent.

That might seem disheartening to the Americans who earn less than these supersavers or who don't have access to a retirement account or company match.

Still, here are some pointers worth gleaning from these supersavers:

Assign jobs to your money: Supersavers "designate certain pools of money for certain jobs," UBS Wealth Management Americas managing director Jason M. Katz told The Times. That's also a tenet of a budget program that has gained a cult following. Called You Need a Budget, it advises consumers to "give every dollar a job." The idea is to plan out in advance how you'll spend your paycheck, creating a plan for short-term and longer-term spending goals.

One reason budgets often fail is that they're too restrictive and don't leave money for the extras that can make people feel like they can have fun. Reining told The Times that even though he has cut out some expenses, like taking flying lessons, he goes on overseas vacations each year, such as trips to England and Italy.

Have a long-term retirement goal: Having a clear goal of what you want -- or need -- to save is often a common thread among supersavers. For Reining, that meant having at least $1 million in his brokerage account. Long-term goals can also help investors make mistakes such as getting wrapped up in the latest investment fad, the CFA Institute notes. Short-term views can lead to bad investing habits such as skipping out on an asset-allocation strategy or trading too much and too often, the organization says.

Pay yourself (more) first -- and make it automatic: Paying yourself first is a well-known adage for how to approach retirement savings. But supersavers use two techniques to increase their funds: They boost the share of their income they're socking away, and they use an automatic transfer from their paychecks to their retirement accounts. For workers without employer-sponsored accounts, the same type of automatic transfer can be set up through an IRA account at a brokerage.

Reining said he started small, boosting his savings from 4 percent of his income to 10 percent. Eventually, he raised it to more than 50 percent of his paycheck.

Focus on fees: Fees can take a bite out of your retirement income, so it's important to be aware of what advisory or fund management fees you might be paying. Fees for a median-income two-earner family can eat up almost one-third of their investment returns over a lifetime, according to Demos, a think tank. Reining wrote on his blog that he invested in index funds, which typically have lower fee structures than actively managed funds, and individual stocks.

Learn from your andothers' experiences: Having a bad experience, such a financial loss, can be helpful if it makes you more open to learning from your problems. That can help people decide to set a retirement goal, a budget or get realistic about their plans. Learning from other peoples' experiences can help as well, given that many supersavers have friends with similar goals, creating a sort of "supersaver cluster," the CFA Institute's Robert Stammers told The Times. Peer pressure can help savers keep on track with their goals, he added.