The Minnesota House signed off late Saturday on a proposed constitutional amendment to ban gay marriage, clearing the way for voters to decide the issue in 2012.

After nearly six hours of emotional debate, mostly from ban opponents, the House voted 70-62 to approve putting the question on the statewide ballot next year. A handful of Republicans joined all but one Democrat in voting against it.

State law already prohibits gay marriage, but supporters of the proposed amendment said it's necessary to prevent judges or future lawmakers from making it legal in Minnesota. Critics said the plan is divisive and would put discrimination into the constitution.

The amendment would define marriage as only between a man and a woman. The state Senate already passed the measure. Democratic Gov. Mark Dayton has no power to block it from the ballot, but said before the vote Saturday that he would fight its passage. Dayton called the amendment "un-Minnesotan."

Rep. Steve Gottwalt, the bill's sponsor, said voters should have the final word on the issue.

"This is not about hatred. It is not about discrimination or intolerance," said Gottwalt, R-St. Cloud.

But another Republican, Rep. John Kriesel, described how losing his legs in Iraq began a personal transformation of his views on the issue. He said he would have supported the amendment five years ago, but has since realized that the country for which he fought should not deny the right of two people who love each other to marry.

"I'm pleading with you to vote no," said Kriesel, R-Cottage Grove. "I'm begging you."