"Men and women with same sex attraction have every right to live as they choose, they don't have the right to redefine marriage for the rest of us," said Jennifer Roback-Morse of the National Organization for Marriage.
"The people of this country want marriage protected. They want their votes to count and unelected judges and activist legislatures should not redefine marriage," said Brian Brown, also of the National Organization for Marriage.
A New Jersey Supreme Court decision four years ago ruled that gay couples must have equality and the state began civil unions. A legislative effort to legalize gay marriage while Jon Corzine was governor failed and Gov. Christie is against it.
But gay rights groups say the word 'marriage' is what the world recognizes, while civil unions are confusing and misunderstood.
They've gone back to court to challenge the law.
"Civil unions have been an abominable failure when it really matters," said Jay Lassiter of Cherry Hill.
Hayley Gorenber of LAMBDA Legal said civil unions "Cause and invite discrimination from all quarters. From government, businesses, schools and medical providers."
To counter the anti-gay marriage demonstration outside, Garden State Equality held an event of its own where gay couples, and their children, talked about the need for same sex marriage.
"We're a normal loving family and we deserve all the right that every normal family gets," said Miriam Fried of Millstone, New Jersey.
Right now gay marriage is legal in five states and the District of Columbia. Supporters are hoping to add New Jersey to that list.
The National Organization for Marriage promises to do whatever it can to stop it.