The Minnesota Senate on Wednesday approved a voter referendum to amend the constitution to ban same-sex marriage.
The measure was approved by a vote of 38 – 27, with only one Democrat joining Republicans in supporting the amendment.
Minnesota law currently defines marriage as a union between one man and one woman, but proponents say that a constitutional amendment is necessary to protect against same-sex marriage being legalized by a court.
The measure must now be approved by the House of Representatives, where it is expected to pass. If approved, it will go before voters in November 2012.