An amendment to the commonwealth’s constitution that would explicitly ban gay marriage and civil unions has a comfortable 53 percent to 43 percent lead among likely voters, according to the latest WaPo poll.

A majority of Virginians support a proposed constitutional amendment that would ban same-sex marriage and civil unions, although voters split on the measure when presented with interpretations of its potential impact, according to a new Washington Post poll. Fifty-three percent of likely voters said they would vote for the amendment, and 43 percent would oppose it, the poll found, indicating that three weeks before Election Day opponents still have a long way to go to make Virginia the first state in the country to defeat a same-sex marriage amendment.

The only part of the state to oppose the measure was Northern Virginia, where voters rejected it 55 percent to 42 percent, further evidence that the Washington suburbs have become a political and social world apart from the rest of Virginia. Respondents in the rest of the state backed the measure 58 percent to 38 percent, according to the survey, conducted over three days last week.

Northern Virginia is, for all intents and purposes, a separate Blue State geographically melded atop a solid Red State. The DC suburbs and exurbs are the richest and fastest growing part of Virginia, consisting almost entirely of transplants (like my wife and I) who came for jobs that wouldn’t exist except for the proximity to the nation’s capital.

The results on the gay marriage amendment would seem to be good news for Republican incumbent George Allen in his bid to stave off Democrat convert Jim Webb. While the same poll shows Allen with only a two point lead, within the margin of error, one would think it unlikely that many would simultaneously vote to ban gay marriage and to send a Democrat across the Potomac. Oddly, a surprisingly strong percentage say they will.

Seventy-three percent of people who also said they would vote to reelect Allen backed the amendment, and 23 percent said they’ll vote against it. Two-thirds of those who support Allen but oppose the amendment are women. Among those who said they would vote for Democrat James Webb for U.S. Senate, 67 percent opposed the measure and 31 percent supported it. Allen favors the amendment, and Webb is opposed because he thinks the language goes beyond prohibiting same-sex marriage. Webb believes marriage is between one man and one woman.

The only group to significantly cross party lines was blacks. In the poll, blacks supported Webb by 81 percent to 11 percent, but they favored the amendment 61 percent to 34 percent. “I don’t believe in gay relationships; I just don’t believe that they are right,” said Aaron Moore, 26, from Chesapeake, who added that he follows the Pentecostal faith and will vote for Webb. “Even though I’m a Democrat, it’s just something that I disagree with most Democrats on.”

The last stat isn’t particularly unusual. Blacks tend to be far more socially conservative than other Democratic subgroups but are nonetheless among the most loyal to the party.