With just over a week until the election, the multimillion-dollar fight over a constitutional amendment to ban same-sex marriage remains a statistical dead heat, according to a new Star Tribune Minnesota Poll.

The race appears to have tightened slightly, with a slim plurality of Minnesotans continuing to favor the amendment. But that support falls shy of the 50 percent needed to change the state Constitution.

The poll results are nearly identical to a September Minnesota Poll, leaving both sides clawing for the few remaining undecided voters.

Among likely Minnesota voters, 48 percent support the amendment, down 1 percentage point from late last month. Another 47 percent of Minnesotans oppose the change, the same as a month ago. Just 5 percent of voters remain undecided. Minnesota law requires any change to the Constitution to capture a majority of all ballots cast. That means a ballot in which the voter skips the question is counted as a no vote, a twist that could become critical in the deadlocked race.

Amid a blitz of TV advertising and other spending by both campaigns, the poll is the latest sign the race will be the most expensive and divisive ballot question in state history. The survey found few pockets of voters who have not made up their minds.

The poll shows that people who have a friend or family member who is gay or lesbian are more likely to oppose the amendment.

Among those who plan to vote no, 54 percent know someone who is gay or lesbian. For those who would vote to change the Constitution, 40 percent say they have gay or lesbian friends or relatives.

The sampling also found that Minnesota's faith leaders are enormously influential.

Fully 70 percent of supporters say their religious leader helped inform their decision on the question; 26 percent say their faith leader had little or no impact. Among amendment opponents, 27 percent said a faith leader played a significant role in their position.

Both campaigns expressed confidence in their ability to win.

"The history of polling on this issue shows that support for our side is always under-represented in the polls and the position of our opponents is overstated," said Frank Schubert, campaign manager for Minnesota for Marriage, the lead group pushing the measure. "If that dynamic plays itself out in Minnesota, as I expect it will, we will have a strong win."

Opponents of the amendment have been working feverishly for more than a year to make Minnesota the first state to prove Schubert wrong.

"When Minnesotans go to the polls, they'll measure this amendment against their values of freedom and treating others as you would want to be treated," said Richard Carlbom, campaign manager for Minnesotans United for All Families, the lead group trying to defeat the measure. "This amendment just doesn't stack up to our values as Minnesotans."

The amendment would constitutionally define marriage as a union between a man and a woman. Minnesota law already prohibits same-sex marriage, but supporters worry that future courts or Legislatures could change the law.

A state divided

The poll points up a stubborn division among voters based on age, where they live and political leaning.

Republican men living in the suburbs are among the amendment's strongest supporters. The core of opposition comes from voters who are under 35, urban and Democratic.

Among suburban votes, 54 percent say they support the measure compared to 39 percent who are opposed. But the poll also found that 7 percent remain undecided -- the largest single bloc of Minnesotans who haven't made up their minds.

In the Twin Cities, the numbers flip. Minneapolis and St. Paul continue to be a stronghold of amendment opposition, with 56 percent of voters there saying they will reject the measure and 39 percent planning to vote yes. About 5 percent of Twin Cities voters remain undecided.

In outstate Minnesota, 53 percent of voters say they support the measure, while 44 percent will vote no. Only 3 percent are undecided.

"I go to a Christian church and as far as everything I read in the Bible, a marriage is between a man and a woman," said Brad Nelson, a 54-year-old farmer from East Grand Forks.

Nelson said he knows gay people in his community and doesn't have a problem with them so long as they keep to themselves. "As far as a gay person getting married, I don't think that's the way it is supposed to be," he said.

The state's youngest voters are the strongest amendment opponents and the most likely to have their minds made up.

Among voters 18 to 34, 54 percent say they are voting to defeat the amendment, while 44 percent support it. Older voters are next most-likely to oppose the measure. Among voters 65 and older, 51 percent say they are voting to defeat the amendment and 43 percent support it.

The strongest amendment support comes from voters 35 to 49, of which 55 percent say they will vote yes.

Party identification remains another fault line.

Fully 85 percent of Republicans support the amendment compared to 78 percent of Democrats who oppose it.

The race has tightened among independents, who are crucial to the outcome of any election.

Forty-eight percent of independents want the change to the Constitution and 47 percent don't. A month ago, independents favored the amendment 55 percent to 38 percent. Only 5 percent have not picked sides, down 2 percentage points from a month ago.

Gender continues to show a reliable split, with 54 percent of men favoring the amendment and 52 percent of women opposed.

"What's the point of voting for something when it is already a law?" asked Jennifer Collis, a 25-year-old Democrat from St. Paul. She will be voting no, calling the proposal "a giant waste of time."

Baird Helgeson • 651-925-5044