Strategist believes bull still has room to run

Brian Belski, chief investment strategist at BMO Capital Markets, says the current bull is part of a long-term, secular uptrend in stocks.

The bull, he says, has legs, and is "transitioning" into a new more bullish phase. "Welcome to the bull market," he says.

One big reason Belski thinks stocks can keep rising (although don't expect a straight line up, he says) is because the market is moving into the second phase of a three-part story.

The market, which made history last week when the Standard & Poor's 500 closed above 1700 for the first time, is exiting the "reactionary," or disbelief, phase and going into the midcycle "acceptance" phase.

In the acceptance phase, Belski says, investors start thinking in the following way: "You know what? I can buy stocks again. The stock market is not the evil empire. They are not going to hurt me." In this stage, money moves back into the stock market, creating a tailwind in the form of greater demand.

The good news is the stock market is far from the bull market-killing "euphoria" stage, when everyone and their uncle is in the market, and there is no one left to buy. The stock market only has one way to go: down.

"We are nowhere near the euphoria stage," says Belski.

That doesn't mean there won't be pullbacks or headwinds, he says, such as rising interest rates' potential impact on housing, angst about a federal budget deal or stocks struggling in a historically weak seasonal period.