Governor Mark Dayton on Tuesday made Minnesota the nation's 12th state to allow same-sex couples to marry and only the second in the Midwest, signing a bill on the steps of the state Capitol before thousands of supporters.
The Democratic governor's signature came a day after state senators approved the bill, which made Minnesota the third state this month to approve same-sex nuptials after Rhode Island and Delaware.
The Minnesota law takes effect on August 1 and Minneapolis, the state's biggest city, said on Tuesday that City Hall would open just after midnight on the first day same-sex couples can marry and Mayor R.T. Rybak will be on hand to officiate that night.
"It is now my honor to sign into law this next step for the state of Minnesota to fulfill its promise to every Minnesotan," Dayton told the crowd in St. Paul before signing the bill flanked by its key Democratic sponsors, Senator Scott Dibble and Representative Karen Clark.
Iowa is the only other Midwestern state that permits same-sex couples to marry, by a state Supreme Court order in 2009.
Opponents of the bill questioned whether the rights of religious groups and individuals who believe marriage should be only between one man and one woman will be protected. They also questioned the speed of the law's adoption.
The votes were a sharp reversal for Minnesota's legislature.
Two years ago, Republicans controlled both chambers and bypassed Dayton to put forward a ballot measure to make a state ban on gay marriage part of the Minnesota constitution.
Minnesota voters in November rejected that measure and voted in Democratic majorities in both the state House and Senate, setting the legislature on the path toward Monday's vote.
"What a day for Minnesota, and what a difference a year and an election can make in our state," Dayton said. "Last year, there were concerns that marriage equality would be banned here forever. Now, my signature will make it legal in 2-1/2 months."
Also in November, voters in Maine, Maryland and Washington state approved same-sex marriage laws. Same-sex couples are also allowed to marry in Massachusetts, Connecticut, New York, Vermont, New Hampshire and the District of Columbia.
Illinois lawmakers have been considering a same-sex marriage bill. Illinois senators approved a bill in February, but the measure has not been voted on in the full House.
(Reporting by David Bailey; Editing by Cynthia Johnston and Eric Beech)