Steve Lonegan, the Republican candidate from New Jersey vying for the U.S. Senate, has described gay parenting as a “biological phenomenon.”

Appearing opposite his Democratic rival, Newark Mayor Cory Booker, during a televised debate on Wednesday, Lonegan was asked his position on marriage for gay and lesbian couples.

“Marriage between a man and a woman is the greatest institution ever devised by the minds of man to raise a child,” Lonegan answered. “And that's what this is about. It's about children. And I'm going to support traditional marriage.”

(Related: New Jersey judge won't delay order legalizing gay marriage.)

“However, I do believe in liberty and the rights of adults to live their lives the way they choose. Consequentially, I do not want other groups forcing their new value system down the throats of my Catholic Church, evangelical church, protestant churches, and overriding our institutional religious beliefs.”

Booker, a long-time supporter of marriage equality, insisted that the government must treat all citizens equally.

“And this is the problem: He says that he supports liberty but you can't be free to marry who you love. He says he supports liberty but he wants politicians getting between a woman and her doctor about making their own health care decisions.”

In a follow up, moderator Jim Rosenfield asked Lonegan: “You said this is about children. So are you saying same-sex couples should not be allowed to have children?”

“That would be a biological phenomenon,” Lonegan answered, apparently unaware that in some states up to twenty-six percent of gay couples are raising children, some from previous relationships.

(Related: Mississippi tops states with gay parents.)

“There is adoption. There is artificial insemination ...”

“I have a question about how healthy that will be in the long run for those children. And I have mixed feelings about that. I will admit I have mixed feelings about that,” he answered.