Tax reform is the "next big thing" for the stock market, even if the corporate rate isn't slashed to President Donald Trump's target of 15 percent, O'Shares ETF investment chairman Kevin O'Leary told CNBC on Monday.
"We may not get 15 percent, but if we get 22 percent it's going to bring the market up another 10 to 15 percent. That's what I'm betting on," the "Shark Tank" star said in an interview with "Closing Bell."
The current federal corporate rate is 35 percent.
Republicans have shifted their focus to cutting taxes after failing to pass their bill to repeal and replace Obamacare. The White House and GOP leaders are expected to tout tax reform in speeches and events during the next few weeks.
While the Trump administration has said it hopes to see a bill introduced in September, some Republican lawmakers have suggested that timeline is overly aggressive.
Meanwhile, Oliver Pursche, chief market strategist at Bruderman Brothers, sees a number of factors that are positive for the market.
For one, "you've got an environment where you had got 10-plus percent earnings growth for the S&P," he told "Closing Bell."
He also cited the possible delay of Federal Reserve interest-rate hikes thanks to low inflation and a decent, growing economy. Plus, the fourth quarter tends to be one of the strongest for the market, he said.
"There's lots of reason to be optimistic," said Pursche.
On Monday, U.S. stocks closed sharply higher as geopolitical tensions surrounding North Korea eased.
— CNBC's Ylan Mui and Fred Imbert contributed to this report.
Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank," which features Kevin O'Leary.