MADISON, Wis. -- A majority of Wisconsin residents said that they support a proposed state constitutional amendment that would clearly define marriage as between a man and a woman, according to a new WISC-TV poll.

Fifty-one percent of those in the statewide survey said that back the amendment that would effectively bar gay marriage or civil unions. Forty-two percent said that they oppose the measure. Seven percent said that they're undecided.

The 9 percentage point gap is about the same as similar polls that were conducted in August and September. The October poll is the third in a series of four preceding the November election.

The margin of error is plus or minus 4 percent. The telephone poll of 600 likely voters was conducted by Research 2000 from Oct. 2 to Oct. 4.Besides the marriage amendment, the poll also asked questions about the races for governor and attorney general.