Democratic U.S. Sen. Robert Menendez led Republican rival Bob Hugin by 15 percentage points among likely voters in a poll released a day before New Jersey voters go to the polls. Menendez was ahead of Hugin, a former Celgene Corp. executive, 55 percent to 40 percent in a Quinnipiac University poll released Monday. It was the second straight survey to give him a double-digit lead after several polls showed a tight race. A Stockton University poll released Friday had Menendez ahead, 51 percent to 39 percent. Menendez never trailed in any survey.