"I have not decided," Cooperman said on "Squawk Box." But the Omega Family Office chairman added that, "this election, in my opinion, is pivotal in the long-term outlook."
Cooperman — a vocal critic of Sen. Elizabeth Warren during her unsuccessful bid for the Democratic presidential nomination, castigating her wealth-tax proposal as "probably unconstitutional" — said he wants to hear more from Biden on his personal ideology.
"We have to make sure that we stay as a capitalist nation. Everybody thinks that Biden is a socialist. I don't think so, but he's got to speak out. He's got to speak out loudly and clearly what he stands for," Cooperman said.
Cooperman also has been critical of Trump, suggesting last fall in a CNBC interview that Trump should consider not running for reelection if he didn't become "a president for the entire country and not just his base."
In explaining why he remains undecided, Cooperman said Monday of Trump, "the bottom line is we have a man with limited character who has good economic ideas, but he's very divisive in his dialogue."
On the other side, "we have a man of decent character who I'm not sure what he stands for," Cooperman said of Biden.
"That's the craziest thing I heard. If he can't debate President Trump, who the hell is going to vote for him?" Cooperman said. "It's up to him to address the issue of law and order. It's up to him address the issue of capitalism versus socialism."
Expressing concerns about Biden taking stances to appease the far-left wing of the Democratic Party, Cooperman suggested that he's "surrounded by socialists." He said Biden "seems like a good man, but we've got to make sure he's strong and resolute in his views."
Cooperman — a major philanthropist who has signed The Giving Pledge created by Bill and Melinda Gates and Warren Buffett — emphasized that he recognizes his good fortunes and is willing to be taxed. "I'm willing to work six months a year for the government and six months a year for myself. I think that's fair," he said. But, he added, "I just get driven up a pole when these politicians talk about 'paying your fair share.' What do they have in mind?"
Cooperman, the son of a Bronx plumber, has mostly donated to Republican candidates in recent years, according FEC data. But in 2016, he donated $1,000 to Democratic presidential nominee Hillary Clinton. He donated $2,700 to Republicans Jeb Bush and $2,000 to Sen. Marco Rubio earlier in the 2016 campaign cycle.