The Minnesota House will hold a final floor vote on whether to legalize same-sex marriage Thursday.
House Speaker Paul Thissen, DFL-Minneapolis, said he would not bring the measure up for a floor vote until he was certain it had the votes to pass.
The Senate is expected to take up the measure soon after. DFL Gov. Mark Dayton is a supporter of same-sex marriage and said he will sign the proposal into law.
The vote will come after months of intense lobbying at the Capitol by both sides of the issue.
"Thursday's vote in the Minnesota House of Representatives will be a historic victory for thousands of same-sex couples and families in our state," said Richard Carlbom, campaign manager for Minnesotans United, the lead group pushing for same-sex marriage.
If legislators pass the measure, Minnesota will become the 11th state to legalize same-sex marriage.