After a long, passionate and solemn debate that lasted deep into the night, the Minnesota House passed a proposed constitutional amendment on Saturday to define marriage as the union of one man and one woman.

Voters will decide the question in November 2012. The final vote was 70-62. Four Republicans voted no. Two Democrats voted yes.

"I do not believe it is up to judges or even this body, but it should be up to Minnesotans," said Rep. Steve Gottwalt, R-St. Cloud, sponsor of the bill. But he said his beliefs are not paramount: "It is not about what I think. It is about what we think as Minnesotans."

In personal, sometimes tearful speeches, opponents said the amendment is wrong.

"Members, I understand discrimination. I have experienced discrimination. And have felt discrimination," said Rep. John Ward, DFL-Brainerd, who often holds his microphone in a shrunken hand. "If you think there is a tiny bit of discrimination in this amendment, I beg you, I ask you, I implore you to vote no."

The amendment question will set off multimillion-dollar campaigns from both sides. It also is expected to draw in national donors, operatives and attention, as did campaigns in several dozen other states that have voted on the issue.

Minnesota law already bans gay marriage, but backers of the proposal say only a constitutional amendment could keep courts from deciding the issue. An amendment also works around DFL Gov. Mark Dayton, who said he opposes it with "every fiber" of his being. Governors have no veto over constitutional amendments passed by a legislative majority.

In other states, marriage amendments have passed. But the mood on gay marriage may be changing. According to a recent Star Tribune poll, a slim majority in the state opposes the proposed amendment.

With the GOP now in control of the House, it had seemed a near certainty that lawmakers would approve the amendment earlier this year. The Senate passed it two weeks ago, 37-27, with all Republicans and one Democrat voting yes. Since then, the situation in the House had become less clear.

Advocates for both sides pressured lawmakers, and the mood became more tense at the Capitol. Social conservative activists and donors have made amendment passage a key priority and made that clear to the members they helped elect. Gay rights groups were equally adamant, prompting thousands of Minnesotans to camp outside the House chamber for days, chanting, singing and cheering.

Heightening the tension, on Friday, Bradlee Dean, a firebrand pastor, took to the House rostrum to give a two-minute opening prayer as a guest chaplain. His prayer and his history, which includes advocating for jailing gay people, set off a firestorm. In an emotional speech, House Speaker Kurt Zellers, R-Maple Grove, apologized and denounced Dean and his words.

The uproar cast the vote even further in doubt.

But Saturday afternoon, with a few hours notice, House leaders decided it was time to vote.

Quiet prevails

The usual din of conversation, laughter and paper rustling was absent during much of the debate. At one point during the critical vote to send the measure back to committee, the room fell dead quiet as the vote board lit up, except for the slow squeak of a chair. Through the night, lawmakers on both sides of the aisle and the issue, turned in their chairs to catch every word.

Gottwalt sat quietly, intently listening to each speaker. As opponents spoke of their views, telling of their own experiences with anti-Semitism, racial discrimination, military service, love, pain and values, he listened.

Other than Gottwalt, no amendment supporters spoke. Late in the night, Republican Rep. Rod Hamilton told his colleagues of his struggle deciding how to vote. He ended up voting yes.

Freshman Republican Rep. John Kriesel, an Iraqi war veteran, broke with his party early this session by clearly, publicly and passionately proclaiming the amendment was wrong.

On the House floor Saturday, GOP Rep. Tim Kelly, who also opposes the amendment, pressed him for his story. Kriesel, who has become a hero among amendment opponents, told his colleagues that he lost his legs in an explosion during combat patrol. He wanted to defend his country and help the oppressed, he said.

Hours later, he returned to stand on his prosthetic legs to tell his colleagues of Andrew Wilfahrt, whose photo Kreisel distributed. Wilfahrt was a Minnesota soldier, killed in Afghanistan. He was gay.

"I cannot look at this picture ... and say 'you know what, Corporal, you were good enough to fight for this country and give your life, but you were not good enough to marry the person you love,'" Kriesel said.

"This amendment doesn't represent what I went to fight for," Kriesel said.

"Hear that out there?" he said of the cheers that arose when he and other opponents spoke. "That's the America I fought for and I'm proud of that."

He said he would have pressed a "Hell No" button if he had one.