A proposed constitutional amendment in Minnesota which would define marriage as a heterosexual union is losing steam just weeks before voters head to the polls.

According to a Public Policy Polling (PPP) survey of 937 likely Minnesota voters conducted from October 5th to 8th, 46 percent of voters support the amendment, while 49 percent say they are opposed. That's a 2 percent drop in support from a survey conducted last month.

The measure has lost support from independents, who flipped from supporting the amendment 51 to 42% in September to opposing it by a 52- to- 42% margin.

“The marriage amendment in Minnesota continues to look like a toss up,” said Dean Debnam, president of Public Policy Polling. “Voters are very closely divided on the issue.”

The amendment needs 50 percent approval to pass.

Pollsters found that 47 percent of voters support gay marriage, while 43 percent remain opposed.

A large majority (74%) of Minnesotans support either marriage (43%) or civil unions (31%) for gay couples. Twenty-four percent said there should be no legal recognition of such unions.

A majority (52%) of Republicans support either marriage or civil unions for gay couples.