Sen. Bernie Sanders (I-Vermont) has a something of a surprising new fan: Warren Buffett.

In an interview on CNBC on Tuesday, the billionaire investor said that he admires the way that Sanders has run his campaign.

"I think Bernie Sanders has been a terrific campaigner. He campaigns exactly as I would campaign if I were a candidate," Buffett said.

Buffett's support is interesting considering the investor has said he's not a "card-carrying Democrat." And if Sanders had his way, Buffett would likely see an enormous tax increase that goes far beyond the tax-reform proposals that Buffett supports.

Buffett cited Sanders' refusal to criticize Democratic presidential front-runner Hillary Clinton, as well as his outspoken opposition to the Citizens United Supreme Court ruling that loosened regulations on political spending by corporations and unions.

"He's not going around saying things about other people. He's just saying, 'Here's my program," Buffett said. "I think he's run a model campaign. He's not going to get elected, but I admire him."

Despite his opposition to the Citizens United ruling, Buffett has seemingly overcome his reluctance to donate to so-called super PACs, pledging to vote for Hillary Clinton and donating to the "Ready for Hillary" group in 2014.

In the interview on Tuesday, Buffett also said that it was a mistake for Clinton to make jokes about the controversy surrounding her use of a personal email address and private server while she was secretary of state.

"I don't think it was the best way to handle it," Buffett said.

The Berkshire Hathaway CEO reaffirmed his support for Clinton's policies, and said that the email scandal was not particularly concerning for him. He has committed to vote for Clinton in the 2016 election.

Buffett isn't just watching the Democratic side of the field — he also mentioned that he is following along with interest in current Republican front-runner Donald Trump's campaign.

"How can you not watch him?" Buffett said, laughing.