New Hampshire is set to become the fifth state to allow gay marriage.
The state Senate approved legislation Wednesday already passed by the House.
Family policy groups tell CBN News it is a defeat but the fight is not over.
"So now the bill goes to the governor's office and the governor has repeatedly stated that he does not support same sex marriage, that he's opposed to it. And we hope now he stays true to his word and vetoes the legislation," Kevin Smith Cornerstone Policy Research said.
Smith said the family policy groups have overwhelming support in the state against same sex marriage.
Massachusetts, Connecticut, Vermont and Iowa already allow gay marriage. Several other states are expected to take up the issue this year.