Warren Buffett likes giving away his money and he likes being involved in the nation's political debate. But he won't become a Democratic version of the Koch Brothers, giving away millions of dollars to his favorite candidates.

Buffett has given $25,000 to Ready for Hillary, a Super PAC that's backing Hillary Clinton's expected run for the White House. He strongly supports her and expects she'll win. But she'll have to do so without a six-figure check from Buffett, even if he can easily afford to write one.

"I support her, but I would not write a huge check," he told CNN. He plans to help raise money for her campaign, but says he doesn't believe in the kind of huge donations that current campaign laws allow.

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"I just don't believe that the elections should be decided by the super-rich," he said. Being a billionaire, he has said, shouldn't mean he can "outshout everybody else."

"Obviously it's very tempting to take a very big check from somebody who has a special interest. [But] it's counter to our ideas of democracy to allow unlimited campaign contributions."

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Buffett is the second-richest American, according to Forbes, worth an estimated $67 billion. David and Charles Koch are tied for fourth on the list with $42.9 billion each.

Buffett has made a total of $329,000 in political donations since 2000, according to the Center for Responsive Politics lists donations, including the $25,000 to Ready for Hillary.

The Koch brothers have reportedly told a group of conservative donors that they plan to spend $889 million during the upcoming 2016 campaign alone.

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Buffett said he wasn't aware when he made that contribution that the group qualified as a Super PAC. Buffett is one of nearly 100 donors to give $25,000 to the group.

"I think of Super PACs as these things with donations of hundreds of thousands or millions," he said.

And he said he'll be more careful about contributing to such groups in the future. "I'm not for Super PACs,' he said.