A Minnesota constitutional amendment that would ban gay marriage in the state cleared the Senate on Wednesday.

Republicans and one Democrat, Senator Leory Stumpf of Plummer, banded together to approve Republican Senator Warren Limmer's bill with a 30 to 27 vote after three hours' wort of often-emotional debate. A companion House measure has already cleared its first legislative hurdle and is also expected to pass.

If approved, voters would be asked in 2012 to decide on the definition of marriage. Minnesota law already bans gay and lesbian couples from marrying, but supporters say the law remains vulnerable to legal challenges without the amendment.

Senator Scott Dibble, an openly gay Democrat from Minneapolis, asked, “What's so different about us? What's such a problem?” as he raised a picture of himself with his partner Richard.

“The truth about our relationship is we work hard every single day at our jobs,” he added. “We've been there for each other. We made a lifetime commitment based in love.”

“What family is this helping?” he added. “Not a single family in Minnesota is helped by this effort.”

Speaking on Friday before a Senate committee vetting his bill, Limmer said the definition of marriage should be decided by the voters of the state.

“I believe and I believe that proponents of the bill believe that this is an issue that is so broad and of an intimate nature that it really should not be in the hands of a court. It should be in the hands of the people of Minnesota,” Limmer said.