Obama has said in the past that he favored eliminating the carried-interest tax break, which lets private equity executives pay the 15 percent capital gains tax on a large portion of their earnings, rather than the top ordinary income tax of 35 percent.

Black said in an interview on the sidelines of a conference that such a move was now likely, adding that it might have come into play even if Romney had won.

"I think carried-interest was on the table whoever won," he told Reuters. "The fact is we have a big deficit and both parties are going to have to look at different sources of revenues."

The carried-interest break, which personally benefitted Republican candidate Mitt Romney, given that he co-founded Bain Capital, costs the U.S. an estimated $18 billion a year.

Overall, Black, who took home $104.2 million in 2011 dividends, salary and share of the profits from Apollo, said the effect of Obama's victory would be felt more at the margins of U.S. business.

"Look, Romney would have been a little more pro-growth in his orientation and Obama will be a little more heavy handed on the regulatory side which will slow growth a little bit but with the status quo of mixed legislature I don't think either is going to have a decisively different effect," he said.

He said he was guardedly optimistic about a potential solution to the "fiscal cliff" under which automatic spending cuts will take effect if a new U.S. deficit reduction deal is not agreed.

"Sometimes necessity is the mother of invention," he said. "In this case I think it has to be."

(Reporting By Christian Plumb; Editing by Louise Heavens)