Mark Cuban is campaigning with VP Kamala Harris in Wisconsin today. What to know about the billionaire businessman, 'Shark Tank' star.

As Vice President Kamala Harris is blitzing battleground state Wisconsin Thursday , billionaire businessman Mark Cuban is campaigning along with her.

Here's what to know about Cuban, including who he is and where he's campaigning:

Who is Mark Cuban? Is he leaving 'Shark Tank'?

Cuban, an entrepreneur, is best-known for being a longtime owner of the Dallas Mavericks and a celebrity investor on the TV program "Shark Tank."

According to the Mark Cuban Companies website , Cuban founded MicroSolutions out of college and sold it to H&R Block. He later co-started the first commercial streaming company, AudioNet, which became Broadcast.com . The company was sold for $5.7 billion to Yahoo! Inc. in 2000.

Cuban acquired the Dallas Mavericks in 2000. While he sold majority ownership last year , he retains a share of the team. According to USA TODAY, Cuban had been one of the league's most prominent owners in the past two decades — and one of the most fined .

A portfolio of Cuban's companies and endeavors, including ones from "Shark Tank" can be found here .

In recent years, Cuban co-founded Cost Plus Drugs , which aims to produce low-cost versions of high-cost generic drugs and disrupt the pharma industry.

Cuban has also been active in the TV and film sphere. According to his "Shark Tank" bio , he co-founded AXS TV and sister network HDNet Movies, the first all high-definition TV network. He co-owns Magnolia Pictures and 2929 Productions, as well as several other entertainment ventures, and previously co-owned the Landmark Theater chain.

As an executive producer, he's been nominated for several Academy Awards, according to his bio.

For his work with "Shark Tank," he's been nominated for eight Emmy Awards, winning one as executive producer for " Outstanding Structured Reality Program - 2024 ."

In 2023, Cuban announced he'd be leaving the show after more than a decade. He'll be making his departure in 2025 after filming Season 16, he previously said in an email to USA TODAY.

"I just want to have a couple summers with my teens before they go off on their own," Cuban said in a statement to The Hollywood Reporter . "Nothing to do with the show. I love it. I love being on it. I love what (it) represents and how it motivates entrepreneurs around the world."

Where Mark Cuban is campaigning with Vice President Kamala Harris in Wisconsin today

Milwaukee and La Crosse.

Later this week, Cuban will be campaigning for Harris in Arizona and Michigan .

Mark Cuban's support for Vice President Kamala Harris

Earlier this election season, when President Joe Biden was still in the race, Cuban told Bloomberg News that he would vote for Biden over Trump even if Biden was on his death bed .

Since then, he's become one of Harris' "leading evangelists in the 2024 presidential election," Newsweek reported , singing her praises in the media . This summer, he became one of more than 100 venture capitalists who threw their support behind the U.S. Democratic presidential candidate, according to Reuters .

Mark Cuban has been a vocal critic of former president Donald Trump

While Cuban has been a continuous vocal critic of Trump over the years, he wasn't always.

"While Cuban has said he was initially a fan of Trump's candidacy when he first announced his intentions back in 2015, he has now soured completely on the former president," Newsweek reported . Trump's ethics dissuaded Cuban, according to The Independent .

Cuban told Newsweek that he thought Trump's first term was bad, but "a second term would be worse."

Cuban often takes to X to be a cheerleader for Harris and push back against Trump, his policies and supporters, including billionaire Elon Musk, founder and CEO of Tesla, SpaceX founder — and X owner.

On X, Cuban recently criticized the comments the former president made about the auto industry at the Economic Club of Chicago.

Does Mark Cuban have political aspirations of his own?

According to USA TODAY , Cuban had floated the idea of running for president in 2020 — even hiring a pollster to gauge his prospects — before eventually reconsidering. He also declined to make a bid later for the 2024 race.

When Newsweek recently asked if Cuban would be interested in serving in a potential Harris administration, he said no because he loves what he's "doing with Cost Plus Drugs and the chance to disrupt all of health care."