Maryland, which just a month ago appeared poised to become the first state in the country to back gay marriage by popular vote, is now reported to be deadlocked on the issue, in part because of a drop in support from religious blacks.

Only a few weeks ago, polls were suggesting that Marylanders were leaning toward supporting gay marriage, but as November approached, the numbers tightened.

The change appears to be partly driven by black pastors in Maryland urging their congregations to vote against the measure.

During a sermon in October, pastor Harold L. Dugger of First Baptist Church in Prince George's County, Md., asked his congregation to go to the polls to cast their votes against same-sex marriage.

"No vote means you've already voted," Dugger told church members. "We stand firmly on the word of God — your faith has to do a lot with what you do at the polls."

A poll conducted in late September for the Baltimore Sun showed the measure to legalize same-sex marriage ahead by 10 percentage points, with more than 50% of African Americans supporting the idea despite a history of opposition from black churches. A quarter of black respondents were opposed.

Since then, voters in Maryland have been exposed to a media blitz, with both sides airing TV ads in an effort to swing undecided voters their way. The latest polling for the Sun, conducted Oct. 20-23 by the Annapolis, Md., firm OpinionWorks, now shows 50% of black voters against same-sex marriage, with 42% supporting the idea.