The leading Democrats have minimal business backgrounds. Maybe that's a good thing.

Among the Democratic presidential contenders, those with a background in the private sector have been notable only for their lack of success with voters so far.

John Hickenlooper co-founded a successful brewing company in Colorado. He's already out of the race. John Delaney was once the youngest CEO on the New York Stock Exchange. His biggest campaign moment was probably when Elizabeth Warren roasted him on the debate stage.

Maybe that's not a bad thing for the economy.

Professor Robert McElvaine has studied businessmen as president. "I was just startled to see how badly things had gone under presidents who were successful in business," he told Yahoo Finance. McElvaine, who teaches at Millsaps College in Mississippi, analyzed data from Herbert Hoover until 2012 and found that "the ones who had been successful in business were pretty much disastrous as far as what happened in the economy."

Jimmy Carter and both President Bushes spent significant time in the private sector and were then criticized for their economic stewardship in office. Harry Truman had a business background as well as economic growth as president; McElvaine notes that Truman “had very unsuccessful business experience.”

McElvaine's 2012 study found a bipartisan trend. Bill Clinton, Barack Obama, Ronald Reagan, Franklin D. Roosevelt and Dwight Eisenhower all had minimal business experience but saw significant economic gains during their terms.

"Things that lead to success in business are not necessarily the things that work in the economy as a whole," he said.

Graphic by David Foster/Yahoo Finance
Graphic by David Foster/Yahoo Finance

Other studies have turned up similar results. A website called the 5minuteeconomist.com ranked post-World War II presidencies based on a metric called the Economic Performance Index, which combines inflation, unemployment, budget deficits, and GDP growth. Reagan, Obama, Clinton, John F. Kennedy, and Lyndon Johnson came out on top. Donald Trump was not yet included in the ranking.

A lack of business experience in the 2020 field

Among the leading candidates looking to replace President Trump, excessive business experience is not a problem.

Sen. Kamala Harris came into politics after being a prosecutor. Sen. Elizabeth Warren's path was via academia. Sen. Bernie Sanders was running for office just a few years after graduating college, as was Joe Biden. The future Vice President, who was barely 30 years old when he was sworn into the Senate, was reportedly talking about becoming president while he was still in college.

One small exception is South Bend Mayor Pete Buttigieg. He worked for about three years as a consultant at McKinsey & Company. During an event at the Commonwealth Club of California in April, he touted his McKinsey experience as a formative one. "I learned how data works," he said, adding that he carried the experience with him into his time as mayor when he "tried to have a more data-driven government at a time when I felt like a lot of decisions were being made by the seat of the pants."

Other candidates with business backgrounds have found some traction in the race. Beto O'Rourke started a web design business in El Paso. He doesn't hide the experience, but his campaign biography focuses just as much attention on his time in a punk rock band as on his firm.

U.S. President Donald Trump departs after speaking to the media about Hurricane Dorian as he returns from Camp David to the White House in Washington, U.S., September 1, 2019.      REUTERS/Joshua Roberts
U.S. President Donald Trump departs after speaking to the media about Hurricane Dorian as he returns from Camp David to the White House in Washington, U.S., September 1, 2019. REUTERS/Joshua Roberts

Andrew Yang has surprised some observers (and handily made the September debate) partly on his pitch of being "an entrepreneur who understands the economy." Yang worked at a health care startup, was the CEO of a test prep company, and founded Venture for America, non-profit to spur entrepreneurship in urban areas. Billionaire Tom Steyer has missed the debate after spending considerable sums of his own money. Steyer and other wealthy candidates face some undeniable headwinds among Democratic voters: "I just don't think people having made fortunes themselves is something that particularly impresses the current Democratic electorate," says McElvaine.

Will 2020 break the trend?

Trump has been an exception to McElvaine's findings so far – stocks have seen significant gains since he took office and unemployment is at record low levels. But if an economic downturn hits in the next year, it would change the president's first-term economic legacy. McElvaine's method analyzes the economic data starting on Jan. 1 of the year after each president took office, arguing that the numbers of the first year of a presidency is better attributed to the preceding administration.

Another 2020 question mark is whether the policies of a farther left candidate like Bernie Sanders – who aims to fundamentally reshape the U.S. economy – would deliver the positive results of his more moderate Democratic predecessors.

U.S. Senator Bernie Sanders speaks at a Our Revolution rally in Boston, Massachusetts, U.S., March 31, 2017.     REUTERS/Mary Schwalm
U.S. Senator Bernie Sanders speaks at a rally in Boston, Massachusetts, March 31, 2017. REUTERS/Mary Schwalm

McElvaine notes that "some of Bernie's ideas are really, pretty extreme.” He adds, "I think Elizabeth Warren, though, understands the economy well. And when she says, ‘I'm a capitalist’, that she is just doing that to distinguish herself a little bit from Bernie and hopefully tone it down on the attacks."

Publicly, Trump is confident he can keep the economy on track into 2020 (and a second term). On Friday he said, "the economy is doing great. The economy is amazing, actually. Worldwide, we’re the number-one by far. Stock market is up again and we’re getting close. We’ll be very close to a new record soon."

Ben Werschkul is a producer for Yahoo Finance in Washington, DC.

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Yahoo Finance All Markets Summit, Oct. 10
Yahoo Finance All Markets Summit, Oct. 10