Donald J. Trump, whose father was a wealthy New York real estate developer and whose firms have gone bankrupt four times since 1993, has argued that his successes as a businessman qualify him for the Oval Office.

"I'm running for office in a country that's essentially bankrupt, and it needs a successful businessman," he once told Rolling Stone.

Trump, the frontrunner in the polls for the GOP presidential nomination, has accumulated an estimated $4.1 billion, according to Forbes. He says he is worth $10 billion. That wealth reflects in some ways the ease with which American parents pass their wealth onto their children.

Trump's father, Fred C. Trump, built an empire of some 27,000 residential units across Brooklyn and Queens, and was worth nearly $300 million at his death in 1999.

It isn't clear to what degree his father underwrote Donald Trump's early career. By the time Donald Trump graduated from college, he was already worth about $200,000 ($1.4 million today), he has written.

In any case, money isn't always the most important thing. It can be difficult to quantify the specific advantages that children inherit from their parents, which can include practical and cultural skills along with social networks.

An American father transmits about 47 percent of whatever advantages or disadvantages he has in income to his son, which is far more than in other developed nations. Across the border in Canada, for example, the figure is about 19 percent.

Americans born into one of the richest fifth of households have about a one in three chance of belonging to the wealthiest fifth themselves by age 26, according to one major study. By contrast, those born into the poorest 20 percent have about an 8 percent chance of making it into that most affluent group.

Another way of understanding these statistics is to compare two young people, one of whom grows up poor but works hard and graduates from college, and another who is born rich but drops out of high school. The one who grew up poor has roughly the same chance of staying poor as the one who was born rich has of staying rich.

Children of the affluent tend to be well off, if somewhat less well off than their parents were. There are, of course, some scions who expand on the wealth they inherit.

Trump can claim membership in this group, as his fortune far exceeds his father's. That's partly because he's been able to use the laws on corporate bankruptcy to shield his assets from the losses he has incurred in business.

A 1983 profile by Marylin Bender in The New York Times described Trump's strategy. He had an eye for what Bender called "good financing," meaning that as much as possible, he'd avoid taking risks with his own wealth.

Sometimes, that meant getting taxpayers to chip in. Trump has bragged about his ability to manipulate public officials into granting him tax abatements and other subsidies.

Early in his career, he was buying lots across the country and improving them on 40-year mortgages from the federal government at 5.5 percent interest. Those terms meant "we didn't have to put up much cash," he told Bender.

On other occasions, he's received favorable loans from private investors.

Not even Trump Tower was built with Trump's money. Chase Manhattan provided him with $24 million in financing to buy the leases, along with a $150 million construction loan.

"He can, thus, add another star to the honor badge of the venture capitalist: for putting up practically none of his own money for an increasingly valuable equity interest in one of New York's most valuable pieces of real estate," Bender wrote.

That deal went well, but later, Trump would run into trouble, starting with the failure of the Plaza Hotel in Manhattan and three casinos in Atlantic City.

As he's often emphasized, Trump himself did not go broke. The firms managing these and other properties these did, and Trump's personal stake in these companies was small enough that he remained solvent.