The Dow Jones Industrial Average plunged more than 300 points into Monday afternoon with Chevron and Exxon Mobil among its biggest losers. But energy stocks won't drag markets down by themselves, McNamee said.
"Energy is only 10 percent of the market. As a consequence, the collapse of those stocks is not necessarily a bad thing," McNamee said.
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McNamee added that oil's low price will benefit more Americans than it hurts. "There is no way" that additional spending money in consumer pockets brought about by cheaper gas won't provide a boon to the U.S. economy, he said.
"It's just plain a huge windfall for consumers," McNamee said.
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McNamee remains cautious on U.S. markets. He anticipates that speculation will continue and a "speculative blowoff" could loom in the near future. The prospect of a "2008-like end" to the current environment lingers in the future, McNamee added.
But oil prices will provide investors with enough reason to hold a positive outlook for now, he said.
"This is going to give investors a reason to not worry and to be more confident about the future," McNamee said.