Top investor: Bull market still in the middle innings

Traders work on the floor of the New York Stock Exchange (NYSE)
Getty Images

John Rogers, chairman of Ariel Investments, believes the third-largest bull market in history may still have room to run.

"We think the U.S. economy is stronger than people think," said the investor, pointing to the seven-year low in the unemployment rate, below-average gas prices, and decent trends in auto and home prices.

Based on his analysis, he believes stocks remain in the "middle innings" of the bull run.

In order to capitalize on that trend he is making a bet on three stocks for the "Squawk Box" Portfolio Challenge.

Below are his top picks and why he is buying them.