(William Thomas Cain/Getty Images)

A Bloomberg poll released Wednesday found that 61 percent of likely voters say that they are "less impressed" with Donald Trump's business expertise based on what they've learned about him over the course of the campaign. About 31 percent say they're "more impressed."

The poll underscores the inherent difficulties of managing a business empire while simultaneously trying to win national office in a highly politicized environment. The numbers come just a week after a separate analysis showed that foot traffic to Trump businesses, including his hotels and golf courses, appears to have fallen significantly during the campaign.

The dim view of Trump's business acumen is likely a function of several things. Trump himself is viewed highly unfavorably by the public, and those negative feelings may cloud voters perceptions of his other professional endeavors as well.

But the rough-and-tumble campaign has brought to light a number of findings about Trump's business career that clash with his public persona as a highly successful business mogul. Among them:

  • Analyses have shown that Trump's real estate investments and other business ventures have drastically underperformed the U.S. stock market over the course of his career. "Had Trump gotten out of real estate entirely, put his money in an index fund based on the S&P 500 and reinvested the dividends, he'd be worth twice as much — $6 billion — today" as he is currently, Max Ehrenfreund wrote last year.
  • Trump's non-real estate ventures have often failed. "Forays into casinos, airlines, professional football and other industries have ended badly," as Ana Swanson outlined in February. To say nothing of his failures in vodka, steaks, and business education.

None of these facts would be particularly damning to a typical businessman. There's nothing wrong with kickstarting a business empire using family wealth, and failure often goes hand-in-hand with entrepreneurship.

It should also be said that Trump has certainly seen his fair share of success. Those billions came from somewhere, after all. He made a lot of money off real estate, and many of his golf courses and hotels appear to have been successful. And his TV show "The Apprentice" has been hugely popular, spawning spinoffs like "Celebrity Apprentice" as well as a whole host of international editions.

But Trump isn't a typical businessman. For decades his personal brand has been built around superlatives: The biggest casinos. The best competitions. The smartest guy in America. And he's brought that superlative sensibility to his campaign, promising to be the "greatest jobs president God ever created." The "healthiest individual ever elected to the presidency." "So good at the military your head will spin."

Above all, as Trump put it in a TIME interview in 2015, "My life has been about winning. My life has not been about losing."

It's one thing to build a business around these types of ideas. But it's a lot harder to do this in a political campaign. You're fighting an opponent looking to tear you down at every possible opportunity. And you're facing a national press corps constantly looking to peel back the curtain separating public boasts from private truths.

For these, reasons presidential campaigns can take a harsh toll on a candidate's favorability or job approval ratings. It's no surprise that the 2016 campaign would have a similarly negative effect on the perception of Trump's business acumen.

A cinematic video highlighting Republican presidential candidate Donald Trump's career played shortly before he took the stage at the Republican National Convention in Cleveland on July 21. (Republican National Convention)

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The real reason Donald Trump is so rich

People who took a gamble on Trump's nomination walked away rich

A secret to Donald Trump’s success that you simply can’t replicate