Strength in energy lifted U.S. stocks on Tuesday as investors concentrated on adding to winning positions as the quarter winds down, but uncertainty kept trading volume light.

The Dow Jones industrial average <.DJI> was up 81.13 points, or 0.67 percent, at 12,279.01, according to the latest available figures. The Standard & Poor's 500 Index <.SPX> was up 9.24 points, or 0.71 percent, at 1,319.43. The Nasdaq Composite Index <.IXIC> was up 26.21 points, or 0.96 percent, at 2,756.89.

(Reporting by Angela Moon, Editing by Kenneth Barry)