Trump will have a block of delegates when the convention arrives, but with the huge field of GOP candidates, it's possible no one will have a majority, Buffett told CNBC's "Squawk Box" in a wide-ranging interview.
"I wouldn't be surprised if [Trump] maintained a quite a solid base for some time," Buffett said—adding that he won't run out of money.
Trump's latest controversial comments were about Fox News anchor Megyn Kelly following Thursday's GOP debate.
According to the latest NBC News Online Poll conducted by SurveyMonkey, however, Trump remains at the top of the list of GOP candidates among would-be Republican primary voters.
The overnight poll was conducted for 24 hours from Friday evening into Saturday.
Buffett—a Democrat and supporter of Hillary Clinton—called the GOP race so far a "spectator sport." He declined to say which Republican he'd like to see Clinton face in the general election.
"If I gave that prediction it would be sort of a kiss of death for the candidate," Buffett joked—saying he'd like Clinton "to run against the whole field."
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