In a surprising show of fundraising force, the two sides fighting over a proposed constitutional amendment to ban same-sex marriage raised a total of $4.5 million since January.

Such strong money-raising in the early months of the campaign shows it to be one of the state's most expensive and unpredictable races of the political season.

Minnesotans United for All Families, the lead group opposing the amendment, has raised $3.1 million from 16,000 contributors, mostly within the state, according to campaign finance reports the group released Tuesday. Contributions ranged from $3 to several $100,000 pledges. The group has raised a total of $4.6 million since forming the campaign last June.

"What this report shows is that the conversation we are having across this state is working, and that more and more Minnesotans are coming to the conclusion that limiting the freedom to marry for same-sex couples is not how we do things in Minnesota," said Richard Carlbom, campaign manager for Minnesotans United for All Families. "Minnesotans know that marriage is about love, commitment and responsibility, and no one would want to be told it's illegal to marry the person you love."

The group pushing a constitutional amendment to ban same-sex marriage in Minnesota has raised $1.4 million since January.

"We are thankful for the strong support of the people of Minnesota in our effort to preserve marriage as the union between one man and one woman in our state Constitution," said John Helmberger, Minnesota for Marriage chairman.

On Nov. 6, voters will be asked whether to approve a constitutional amendment to define marriage as a union between a man and a woman.

State law already forbids legal recognition of same-sex marriages, but supporters want to etch it into the constitution to prevent judges or future legislators from altering the law.

Helmberger said groups supporting the amendments in other states frequently were outspent by opponents, yet they won in 30 states without defeat.

"We are confident that the people of Minnesota will come together to raise the resources necessary to win," Helmberger said.

The group released its overall number on Tuesday, but no details. Campaign finance reports citing individual contributors won't be made available by the state until Thursday.

Along with its totals, Minnesotans United for All Families released a nearly 900-page list of expenses and contributors.

Among the contributors, individual members of the Pohlad family, which owns the Minnesota Twins, gave a combined $305,000. Former New York First Lady Silda Wall Spitzer donated $750. Daniel Wolter, ex-spokesman for Gov. Tim Pawlenty, donated $225.

Star Tribune Media Holdings board chairman Mike Sweeney gave $10,000. The report showed two Star Tribune newsroom employees also contributed. David Hage, a local editor, gave $250; consumer news reporter John Ewoldt gave $170.

After learning of the contributions by newsroom employees, Star Tribune Editor Nancy Barnes sent a memo to the newsroom reminding staffers that "It is critically important to our credibility as a trusted news organization that our journalists refrain from any public political activity including contributing money to a campaign, attending a rally, or putting posters and bumper stickers on your personal property. This covers the constitutional amendment questions as well as campaigns for public office."

Amendment opponents figure they will need to raise upwards of $10 million to win. "We have a very aggressive fundraising plan in place," Carlbom said.

As part of the relentless fundraising push, DFL Gov. Mark Dayton hosted a reception Tuesday evening to kick off the upcoming gay and lesbian Twin Cities Pride festival. He is the first Minnesota governor to host a Pride reception, which also served as a fundraiser for Minnesotans United for All Families.

"We are Minnesotans and we are better than this," Dayton told the crowd of about 300.

He called the amendment battle "a contest for the heart and soul of our state" and vowed to do whatever he could to help defeat the measure.

Carlbom said the group knows that historically, the odds are against them.

"We know that we have a tough road ahead, and we are making strategic investments in continuing this conversation in every corner of the state," he said. "The more Minnesotans talk about this amendment, the more they see that this would limit basic freedoms for some Minnesotans, and the more likely they are to vote no in November."

Helmberger said his group is relying on Minnesotans, not money.

"We don't have to match our opponents' spending; we only need to mobilize people who believe marriage should be protected," Helmberger said. "We have the people of Minnesota on our side, and we remain confident of victory."

Baird Helgeson • 651-925-5044