"We know that every last vote is critically important," Brickman said.
Supporters of the marriage amendment have urged pastors to preach in favor of it during church services this weekend and to remind parishioners not to skip the question, since blank votes count as no votes. Minnesota for Marriage spokesman Chuck Darrell said the group has about 1,500 volunteers aiming to call 100,000 voters a day during the final stretch.
Volunteers working for Democratic President Barack Obama and Republican presidential nominee Mitt Romney were gearing up for Sunday, when Romney running mate Paul Ryan and former President Bill Clinton are both due in Minnesota. Ryan will aim to give the GOP faithful a last-minute shot of energy at the Minneapolis-St. Paul airport, a few hours before Clinton speaks in St. Cloud — his second trip to the state in less than a week.
The visits are a sign of the national interest that has come to Minnesota as Romney makes a late play for a state that hasn't backed a Republican for president since 1972.
"Having Paul Ryan in town no question will continue to motivate people and keep them enthusiastic," state GOP Chairman Pat Shortridge said. Financial problems have forced the party to rely more on volunteers than paid staff in its turnout effort this year.
Clinton's visit also is meant to help Democrat Jim Graves, a hotel magnate who is challenging Republican Rep. Michele Bachmann in an expensive race north and west of Minneapolis funded mainly by the candidates themselves. Graves got help Saturday from Democratic Sen. Amy Klobuchar, a heavy favorite in her re-election bid against Republican Kurt Bills. Klobuchar appeared with Graves at a Democratic-Farmer-Labor Party rally in St. Cloud, while Bachmann visited volunteers at her campaign office there, posting pictures on Twitter.