As he publicly flirts with a run for the presidency in 2020, Mark Cuban has also privately been in touch with potential allies and strategists to plot out a campaign.

The Dallas Mavericks owner confirmed that he has corresponded on multiple occasions since the 2016 election with Steve Bannon, President Donald Trump’s former chief strategist.

He downplayed the interactions in an email exchange with The Daily Beast, saying merely that he “texted with him a few time[s]” and that none, he believed, had “been more than one full sentence.” But according to four sources familiar with their conversations, the two have been in touch for months about a possible 2020 bid. Bannon, these sources say, has encouraged Cuban to run and to consider doing so as a Democrat, seeing it as a realistic path to a viable presidential run.

“They talk regularly,” said Sam Nunberg, a former Trump adviser who is close to Bannon. “They’re very similar. They have a lot of synergy there. Even when [Steve] went to work for Trump, Mark would be interviewed and say nice things about Steve.”

Cuban hasn’t been shy about entertaining the idea of making a run. At an event on Thursday in New York, he said that he if he were to do so, it would be independent of one of the two major political parties. He denied to The Daily Beast that Bannon had personally told him to run as a Democrat but he did note that the Breitbart chairman had suggested he do so to TMZ.

Bannon did not respond to requests for comment on this story. But his discussions with Cuban raise a number of intriguing possibilities about their respective political futures.

For Cuban, the question is whether his name identification, deep pockets, and formidable business background could allow him to run outside of the two major political parties or, perhaps, propel him to victory in a likely crowded field of Democratic candidates.

For Bannon, the question is why President Donald Trump’s one-time top political consigliere would encourage a challenge to his former boss—assuming, that is, that Trump opts to run for a second term. Trump declared his re-election candidacy mere hours after he was inaugurated. But Bannon has reportedly expressed doubts that Trump will stick around for another four years, according to a Vanity Fair report last month.

Cuban is an idiosyncratic political figure. He campaigned for Hillary Clinton and has made various anti-Trump statements this year, recently dubbing the president a “Twitter troll.” Cuban’s politics are a mix of social liberalism, big-business-friendly centrism, and a love of objectivist icon Ayn Rand.

Just two weeks after Trump’s win last year, Cuban and Bannon were spotted sitting down together at the King Cole Bar in New York City’s St. Regis Hotel. Cuban would not go into details about what the two discussed then.

But Bannon is far from the only operative with whom Cuban has spoken about a potential presidential bid. “I’ve gotten more emails than I can count” from people in the political world wondering about his 2020 plans, the Shark Tank host told The Daily Beast.

In fact, Bannon isn’t even the Trump-world figure who Cuban is closest to. That honor goes to Trump lawyer Michael Cohen. As TMZ reported on Thursday, Cuban gave advice to Cohen, a longtime buddy, on how to handle things pertaining to ongoing Trump-Russia investigations. Cuban said he met Cohen for breakfast to help “calm him down and talk him off the roof.”

As Bannon and Cuban have corresponded, the latter has received largely favorable coverage from Breitbart News, the pro-Trump news outlet that Bannon has run since 2012, with a brief sabbatical for his stint at the White House. Cuban even made a March appearance on Breitbart News Daily, the site’s SiriusXM radio show.

“I learn from people who disagree with me,” Cuban told Breitbart. “I want people to challenge me. That’s how I get smarter. That’s how I learn.”

While Cuban made a name for himself as a surrogate in 2016, he lacks a discernable political base. He has never held elected office. And the history of successful Independent presidential candidates is hardly rich. But in the age of Trump, charisma and star power are important electoral traits. It certainly is no longer considered inconceivable for a television host to serve as president. And some of Cuban’s admirers across the political aisle think he could make a legitimate run at the office.

“I think he has a lot of potential for 2020, assuming that the president doesn’t run for re-election,” Nunberg said, saying that Cuban could win the Republican nomination, if Trump is out of the picture. “The way I thought of Trump, people laughed at me… The RNC people laughed at me. Mark has something. I don’t know what it is, but he has something… Trump’s a star, Mark’s a star.”