Billionaire investor Sam Zell predicts that the Trump economy can continue to grow even if the Democrats win the majority in the House in next week's midterm elections.

The economy under President Donald Trump is "doing pretty well," Zell told CNBC.

"I think there's a lot more clarity in public policy. I think there's a lot more clarity in regulation" since Trump took office, the founder and chairman of the property specialist firm Equity Group Investments said. "That clarity translates into a higher level of confidence," he said.

"If the Democrats take back the House, there will undoubtedly be a lot of histrionics and a lot of investigations" of the president, Zell said on "Squawk Box." But with Trump in the White House, "I don't see any significant impact coming from a change in the House other than less gets done."

A Democratic takeover of the House might spook the stock market because of concerns about political instability, including hearings involving the Trump administration, Reuters explained. But the fall in U.S. stock prices this month may be increasingly pricing in such a split Congress, so that scenario may not significantly shake the market.

Even if Democrats win the House, legislative gridlock may reduce the chances of major policy changes if Republicans retain control of the Senate. A Democratic sweep of the House and Senate would likely surprise the market and prompt a sell-off in stocks. The potential for Democrats to alter Trump's tax-cut package or to start impeachment proceedings could jar investor and business confidence.

A Republican win that allows them to retain total control of Congress could lift stocks as it would increase the chances of more tax reform and further de-regulation.

The market would keep one eye on the Federal Reserve though if Congress were to stimulate economic growth further with more tax cuts or spending which may push inflation higher and lead to higher interest rates.

Meanwhile, "rising interest rates is healthy for the real estate economy," Zell said. 

"Very low interest rates took away the sense of urgency and the sense of the need to accomplish things," he said. "There was no penalty to doing it tomorrow."

"I don't think it's raising rates too fast," Zell said of the Fed.

• Sam Zell: Trump Is 'Creating a Lot of Hope' 
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