Ann-Kaner Roth of Project 515, a Minnesota gay-rights group, said she and her fellow activists would take lessons from what happened in New York.

"They were able to build such a broad-based coalition: Republicans, independents and Democrats, the business community all coming out very strongly in support of equality," Kaner-Roth said. "Minnesota is really ripe for that kind of coalition-building."

The anti-amendment coalition is sure to include Democratic Gov. Mark Dayton, who was unable to keep the measure off the ballot but has vowed to campaign against it. He has already appeared at a fundraiser held by amendment opponents and marched in the Twin Cities gay pride parade on Sunday -- a first for a Minnesota governor.