In 12 months, we could witness the Standard & Poor's 500 breaking out above 1,800, says Tom Lee, U.S. equity strategist at JPMorgan Chase.

The upside on the S&P 500 index in the next six to 12 months could be 1,800 or even 1,900 Lee told CNBC.

And "I think we'll ultimately slice through those ... pretty easily," he stated.

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Lee is the most bullish member of the "1700 club," for which membership requires a strategist to be bullish on stocks and to own a year-end price target of 1,700 or higher, according to USA Today.

At the beginning of the year, the 1700 club's roster was empty. Lee was initiated in May, when he revised his initial year-end target from 1,580 to 1,715. On July 26, he renewed his commitment, nudging his forecast higher to own a year-end target of 1,775.

USA Today says Canaccord Genuity strategist Tony Dwyer was the first to join the 1700 club. In March, he raised his target from 1,650 to 1,760.

Dwyer is similarly bullish on the S&P 500's performance next year.

In late July, he expressed confidence in a 2014 target of 1,955. Dwyer says the market is busting myths "including one that says the market is 'already up too much,' and 'it is too late to buy,'" according to USA Today.

Dwyer's bullishness is due, in part, to his beliefs that low economic growth and low inflation will anchor the Federal Reserve to its market-friendly bond-buying programs at least for the rest of this year.

"I think tapering is a bigger deal ultimately for rates and for credit than the equity markets," Lee told CNBC.

He told USA Today his bullishness is "less about the market's momentum" and "more about the economy's momentum."

Lee warned that the markets may be volatile through September, but the bull isn't likely to be slaughtered until the next recession. And that does not appear to be in the forecast any time soon.

"I think it's still profitable to put money to work today," he told CNBC. "There's [also] a really good story on relative value. P/Es [price-earnings ratios] can still expand."

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