Thousands of gay rights supporters rallied outside the Capitol on Thursday to urge the Senate to kill a constitutional amendment that would ban same-sex marriage in Minnesota.

The House approved the addition of the amendment to the November ballot Wednesday.

State Legislators, gay rights advocates and religious leaders spoke to a crowd of more than 3,000 people Thursday to oppose an amendment that would define marriage as between one man and one woman.

The Senate Judiciary Committee will hold a hearing on the amendment tomorrow. If the amendment is also approved by the Senate, it will be placed on November’s ballot for voters to decide whether it becomes part of the Minnesota Constitution.

Ann DeGroot, executive director of OutFront Minnesota, spoke to the crowd and encouraged protesters to meet with legislators.

“We have to let legislators know that we’ll fight vigorously against any attempts to harm our civil rights,” she said.

Rep. Karen Clark, DFL-Minneapolis, the only openly lesbian woman elected to the House, said she was very disappointed with her colleagues for passing the amendment.

“When I walked into the building today, I was full of anger,” she said. “Most Minnesotans don’t know how terrible and extreme this constitutional amendment is.”

But Sen. David Gaither, R-Plymouth, said debating gay marriage rights is not a productive use of his time as a congressman.

“I did not elect office to debate gay marriage,” Gaither said. “It’s unfortunate that we are, as a legislature, engaged in this debate. I don’t know if it’s the best use of our time.”

Gaither said he is not taking a firm stand on the issue at the time but is more in support of adding the amendment than not.

He said he receives more than 100 e-mails per day regarding the issue; 85 percent of them are in support of adding the amendment.

Guest speaker Ann Bancroft, an Arctic explorer who traveled to the North and South poles, said the idea of amending the Minnesota Constitution to include discrimination is ignorant.

“Our positive progress forward is in jeopardy,” she said. “We need to stand firm for what is right.”

Bancroft, who is gay, specifically scolded House Republicans and House Speaker Steve Sviggum, R-Kenyon, for supporting the amendment.

“The Constitution was put in place to protect, not limit rights,” she said.

Sviggum said he supports nondiscrimination in other areas, including the workplace and housing. But the tradition of marriage between a man and a woman is too valuable to go against, he said.

“It’s not a step I can support or will support,” he said.

Sviggum said he believes the Senate does not want to take a stance on the issue and the amendment will not be voted on as a result.

“I have a fear that they’ll try to avoid a vote,” he said. “Hopefully, I’ll be proven wrong.”

St. Paul Reformation Church Rev. Anita Hill said church leaders should not support the amendment.

“There is no room for hatred of any people,” she said.

Many University students attended the rally to show their support for gay rights.

Senior Antonio Cardona, former co-chair of the Queer Student Cultural Center, said politics have become polarized.

“On Monday, they had the governor speaking to them,”

Cardona said in reference to a rally held to support the amendment. “The governor is more into divisive politics and excluding people.”

– Jake Weyer and Molly Moker contributed to this article