The biggest investment opportunity in 2015 may be in cyclical stocks as the U.S. economy continues to improve, veteran portfolio manager Bob Doll told CNBC on Monday.
Technology, industrials and consumer cyclicals in particular could see the biggest gains if the economy shows additional signs of strength, the chief equity strategist at Nuveen Asset Management said on "Squawk on the Street."
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On the other hand, "bond-like equities" such as utilities would probably lag in an improved economy, said Doll, drawing on his 34 years of experience as a portfolio manager.
Separately, investors should expect more volatility as the Federal Reserve begins to raise interest rates, Doll said.