The stock market will celebrate the fifth anniversary of its bull market Sunday, and Sam Stovall, chief equity strategist at S&P Capital, and Jeffrey Kleintop, chief market strategist at LPL Financial, think equities can keep rising.

Of the 11 bull markets since World War II, only three have survived through a sixth year, Stovall told CNNMoney.

But he sees a "good chance" for that to happen this time around, because valuations aren't out of whack. The Standard & Poor's 500 Index has a price-earnings ratio of 16 based on 2014 earnings estimates. That's neither excessively high nor low.

Kleintop tells CNNMoney that stocks can achieve "mid- to high-single-digit gains" before dividends over the next 10 years, though not without increased volatility. So the stock rally isn't winding down, he says. "In fact, the bull market may be getting a second wind."

Stocks will benefit as investors who have been reluctant to enter the market finally take the plunge, Kleintop says. Investors will ultimately realize they can earn more from stocks than safer assets such as bonds, he says.

Others are bullish, too. CNBC commentator Jim Cramer said that while "some stocks are frothy . . . the vast majority are anything but frothy. In some cases they're cheap." And that has created buying opportunities, Cramer said.

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