Cuban, like Trump, is a reality TV star, appearing on ABC's business-themed "Shark Tank," a show that also airs on CNBC.
And just like Trump, Cuban is no stranger to controversy: He has been repeatedly fined by the NBA for his boisterous criticism of referees during games of the basketball team he owns, the Dallas Mavericks.
But this year, Cuban's most striking similarity to Trump is this: He is thinking about running for president.
In an email exchange with CNBC, Cuban revealed his thoughts on the presidency, how he'd structure his campaign and what it would mean for the nation to have, in his words, a "three-comma POTUS—as in $1,000,000,000.
Asked whether he'd ever run for president, Cuban wrote: "I get asked every day. It's a fun idea to toss around. If I ran as a Dem, I know I could beat Hillary Clinton. And if it was me vs. Trump, I would crush him. No doubt about it."
Traditional political candidates, you've been warned.
Donald Trump's polling surge in the race for the Republican presidential nomination has turned the rules of American politics inside out. Things that once were huge liabilities for candidates—massive wealth, limited governing experience, even ego-bursting levels of narcissism—have been turned into strengths.
In an era in which voters are scrambling to signal disgust with politics and politicians, a new set of skills has suddenly become invaluable on the campaign trail, catching traditional candidates flat-footed. Those include the reality TV skills of picking fights and over-the-top self-promotion, as well as the ability to deploy millions of dollars at the stroke of a pen. Remember: while the other candidates at the Iowa State Fair this summer gave traditional speeches next to bales of hay, Trump gave his fans free helicopter rides before telling a small boy: "I am Batman."
In a long-gone political era—circa 2012—the role of billionaires in American politics was to stand on the sidelines as donors, fundraisers and supporters of traditional candidates in blue suits and red ties.
But Trump's rise shows billionaires don't have to constrain themselves anymore. They can cut out the middleman. It's the art of the deal on the campaign trail.
And if you're a billionaire with business sense, a flair for the dramatic and a reality TV background, well, you're within reach of the nomination.
Whatever else Trump does on the campaign trail this year, his legacy just may be in nudging other billionaires off the sidelines and into politics. Just one billionaire is campaigning in 2016. How many will run in 2020?
Forbes magazine lists more than 500 billionaires in the United States. Some of them aren't interested in politics or notoriety. Some are barred from running for president because they weren't born in the country. And some—Facebook's Mark Zuckerberg and Snapchat's Evan Spiegel among them—don't yet meet the Constitution's requirement of being at least 35 years old. (In fact, according to Forbes, there are 12 American billionaires who are too young to run for president.)
But there are likely some native-born, over-35 American billionaires who are watching Trump and thinking: "I can do that."
To Mark Cuban, all this makes sense. Having a billion dollars—that famous "three-comma" net worth—gives a candidate a certain swagger. "Rich people just have a little more arrogance to think we know more than everyone else," Cuban wrote.
And just as John F. Kennedy had an instinctive grasp of the new media—television—that was coming to dominate his political era, Cuban thinks that the social media era will play to the strengths of a different group of candidates.
"There is no question the game has changed and Donald has a much stronger command of it than the rest of the candidates," Cuban wrote. "Most future voters will get their news from their Facebook, Snapchat, Cyber Dust, Instagram, Twitter feeds," Cuban said (Cyber Dust is his own messaging app). "They open their apps and see what's there. They don't go looking for depth and explanations."
"If you as a candidate can't find your way into those feeds, you basically don't exist," Cuban wrote.
But Cuban said he's mindful of the enormous stakes involved in running for president. "No matter how smart or arrogant you think you are, I can't imagine anything more difficult or more humbling than making life or death decisions," he wrote. "Whether it's someone like me, or a Trump, the first time someone dies because of a decision the president made, I think all that bluster goes out the window."
With that in mind, Cuban—who played a fictional president of the United States in "Sharknado 3"—has begun thinking through a campaign platform that skews toward the libertarian end of the political spectrum and focuses heavily on reforming the U.S. economy.
"The first thing I would do is define which social issues were not presidential and instead were personal," he wrote. "They have nothing to do with running the country. They are personal and family decisions."
Instead, Cuban said he'd focus on five top economic problems the country needs to solve.
Those include, he said, income inequality, college debt, overly complex taxes and cybersecurity. "How we deploy bytes and the superiority of our national hackers is far more important than bombs or bullets," he wrote. "You want to stop a bomb? Hack it."
The fifth issue on Cuban's mind is fixing what he sees as broken equities markets. "Investors are ceding control of the markets to stock market hackers," he wrote. "That's a huge problem."
Still, he said, a business background and a billion dollars in the bank would not necessarily make doing the job of president any easier.
"If we have a 3 comma POTUS," he wrote, "It would not take long before the office humbled him or her."
Disclosure: "Sharknado 3" is produced by Syfy, a division of NBCUniversal, parent of CNBC.
CORRECTION: Forbes magazine lists more than 500 billionaires in the United States.