Something funny happened on the way to another huge year for stocks.

With just a week and a half left in 2014, the S&P 500 is up 12 percent, besting nearly everyone's expectations. Still, the best-performing sectors haven't been cyclical stocks that generally rise when the broader market is soaring and the economy is growing.

Instead, health care and utilities stocks have led the way, with 27 percent and 23 percent gains for those sectors, respectively.

Now, the big question is whether that trend will turn around in 2015—setting the stage for a more traditional bull market led by the sort of cyclical stocks that tend to lead in good times and lag in bad.

Over the past year, "people were in search of yield, and that really was the personality of the rally in 2014," said Jim Iuorio of TJM Institutional Services. "What I want to see is things further out the risk spectrum start to rally, and if that's the case, that's when I'll think that we're on a risk-on mode."

BlackRock's Rosenberg: Stocks will beat bonds in 2015



To Jonathan Golub, RBC's chief U.S. market strategist, the key issue is that stocks have surged—even as economic growth has been lackluster.

"The real question is, will the economy grow fast enough to support more economically sensitive cyclical names? This is the ninth year in a row where GDP grew under 3 percent," he pointed out.

In 2015, economists expect growth to finally surpass 3 percent, but "that's been the expectation for each of those nine years, and we haven't seen it," Golub said. "My gut tells me that the economists will prove to be a little bit more optimistic once against."

For that reason, the analyst is looking for the S&P to return 12 to 15 percent, including dividends, once again. However, he says the rally will likely be led by a mix of cyclical and non-cyclical sectors. Specifically, the strategist favors technology and health care stocks, and is less optimistic about industrials.