by Connie Cheng/DPR News

"It's history," reads Minnesota Gov. Mark Dayton's Twitter account.

Minnesota became the 12th U.S. state to legalize same-sex marriage on Tuesday, the third state this month to do so. The Democratic governor signed the marriage equality bill into law, which takes effect on Aug. 1, in front of thousands of supporters.

Dayton signed the bill a day after state senate voted 37-30 in favor of approving the bill. State House approved the measure last Thursday, May 9.

Minnesota's new law comes right on the heels of Delaware, who legalized same-sex marriage just last week.

It was only two years ago when Republicans in Minnesota attempted to pass a state ban on gay marriage. Voters rejected the measure and elected Democrats to take state House and Senate seats, setting the stage to pass the new bill.

The barnstorming for gay rights began in late March, when thousands flocked to Washington D.C. to protest over two marriage laws, the federal Defense of Marriage Act (DOMA) and California's Proposition 8 – both of which are being deliberated by the Supreme Court.

Section 3 of DOMA, which defines marriage as the union between a man and a woman, was found to be unconstitutional in eight federal courts, leading to an appeal hearing by the Supreme Court. The bill was approved during the Newt Gingrich era of Republican leadership in the House and Senate.

The Supreme Court is due to make the final decision on the two same-sex marriage laws in June 2013.