The Standard & Poor's 500 Index broke above 1,800 Monday, and it's only a matter of time before it reaches 2,000, experts say.

The Dow Jones Industrial Index also breached a round number Monday — 16,000. The Dow closed at 15,967 Tuesday, while the S&P 500 finished at 1,788.

It's a no brainer that the S&P 500 should reach 2,000 before the Dow reaches 20,000, as the S&P is 12 percent away from that target, while the Dow is 25 percent away.

Editor’s Note: 5 Reasons Stocks Will Collapse . . .

In addition, "I think that the recent announcement and the market's reaction to [Federal Reserve Chair nominee Janet] Yellen's Q&A on Friday [before Congress] suggest that stimulus is going to be around for longer," Gina Sanchez, founder of Chantico Global, told CNBC and Yahoo's Talking Numbers.

"That is going to benefit smaller companies. The S&P has more small componentry to it than the Dow does."

Richard Ross, global technical strategist at Auerbach Grayson, told Talking Numbers the S&P 500 could reach 2,100.

"While the potential exists for a potential pullback, it's the [S&P 500's] long-term chart that you have to continue to be excited about." he said. "There's a lot of reason to be invested here."

The S&P 500 has jumped 168 percent from its March 2009 low.

To be sure, some investors think the market is at least due for a pause. "We’ve had a big run," Bruce Bittles, chief investment strategist at RW Baird, told Bloomberg.

"My suspicion is that the market might go sideways now for a little while before we encounter a year-end rally in December."

Editor’s Note: 5 Reasons Stocks Will Collapse . . .

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