LOS ANGELES, Aug. 28 (Xinhua) -- A significant majority of likely voters oppose a measure to ban gay marriage, according to a newly-released poll.

    Proposition 8, which would amend the state Constitution to allow marriage only between a man and a woman, is trailing 40 percent to 54 percent among likely voters, according to the poll conducted by the Public Policy Institute of California.

    When asked whether they support or oppose allowing gay men and lesbians to marry, Californians were evenly split, 47 percent to 47 percent, according to the poll published by the Los Angeles Times on Thursday.

    The polling "shows a deeply divided electorate," said Mark Baldassare, president of the policy institute.

    The poll was in line with previous surveys. Support for Proposition 8 has slipped slightly in the institute's poll since a survey last month that showed 51 percent of voters against and 42 percent in favor.

    On same-sex marriage, the poll did not reveal why the split on the ballot measure differed from attitudes on the general issue of gay marriage. But Jennifer Kerns, a spokeswoman for the Proposition 8 campaign, cited the language voters will see on the ballot, which pollsters also read to respondents, that describes the proposition as a measure to "eliminate the right of same-sex couples to marry."

    That legal right has existed since May, when the California Supreme Court ruled that the state Constitution guarantees same-sex couples the same access to marriage that heterosexual couples have. That ruling overturned Proposition 22, passed by voters in 2000, which defined marriage as between a man and a woman.

    The findings are based on a telephone survey of 1,047 likely voters between Aug. 12 and 19. The results have a margin of sampling error of plus or minus three percentage points.