But Stifel’s chief equity strategist Barry Bannister and associate analyst Jesse Cantor have turned the opposite way. They now think the S&P 500 will close the year at 2,300, up 16 percent from Wednesday's close of 1,986.51, Barron's reports. 

They previously forecast a 2014 finish of 1,850 for the index.

Editor’s Note: 5 Shocking Reasons the Dow Will Hit 60,000

Why the about-face?

"The three secular bull markets over six years long, roughly the 1920s, 1950s and 1990s, all coalesced at this exact point before moving higher," Bannister and Cantor write in a report obtained by Barron's.

"While this bull market hasn’t joined the six-year secular club [yet] — that occurs March 2015 — stocks do appear to be consolidating as is normal at this point before potentially moving higher." 

Equity expert Jeremy Siegel, a finance professor at University of Pennsylvania, shares the Stifel analysts' bullishness, though apparently not quite to the same degree.

He predicts that the Dow Jones industrial average will hit 18,000 by year-end, maybe even 19,000. The Dow closed at 16,979.13 Wednesday.

Low interest rates and inflation will combine with strong earnings to boost stocks, Siegel told CNBC. The 10-year Treasury note yielded 2.43 percent late Wednesday, and consumer prices rose 2 percent in the 12 months through July.

Editor’s Note: 5 Shocking Reasons the Dow Will Hit 60,000

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