From NJ.com:

The Rutgers-Eagleton survey shows 49 percent of residents in the Garden State — which traditionally leans Democratic — support the Republican governor’s move, while 42 percent say he should have signed the measure and 9 percent are unsure.

“Most gun control measures we have asked about in the past garner large majorities in support,” said David Redlawsk, the poll’s director and a political science professor at Rutgers University. “This one is different, with residents slightly more in favor of the veto than opposed, perhaps because the change seems only incremental and did not strike gun opponents as significant.”

New Jersey currently limits ammunition magazines to 15-rounds. The bill Christie signed would have lowered that limit to 10-rounds and did not include a “grandfather” clause in it.