Yes, says openly gay D.C. city council member David Catania, a former Republican who holds an at-large seat. According to a website called DCist, Catania is confident that the city council will support the measure when it convenes in January and that the mayor will approve it.
Catania knows his city's politics much better than I, but I wonder whether his confidence is fully justified. Given the strong opposition to same-sex marriage among blacks, as demonstrated most recently in their 70% support for Prop 8, the city council in an overwhelmingly black city might get cold feet as the vote nears. Another open question is whether, even with an enlarged Democratic majority, Congress would overrule the city's recognition of same-sex marriages.