Seventy-eight mayors from U.S. cities large and small gathered in Washington D.C. Friday (20 January) and announced their support of gay marriage.

The group, in the capitol for the annual U.S. Conference of Mayors, included New York City Mayor Michael Bloomberg, Chicago Mayor Rahm Emanuel, Los Angeles Mayor Antonio Villaraigosa (pictured), San Diego Mayor Jerry Sanders and Boston Mayor Thomas Menino.

'If we truly believe in family values, we should value all families,' said Villaraigosa, co-chairman with Sanders and Menino of the campaign Mayors for the Freedom to Marry. 'Denying gay and lesbian couples the freedom to marry weakens society by hurting our communities, neighbors, and families.'

Bloomberg said there has been a positive effect since his state legalized same-sex marriage last year.

'In only a season, the freedom to marry has already made New York a stronger state,' he said. 'This isn't about partisanship or ideology.  It's about extending the freedoms of our country to all people, and ensuring equal protection under the law.'

The joint mayoral effort is part of Freedom to Marry's federal campaign to ratchet up public support for ending marriage discrimination. The group signed a pledge in support of marriage equality for same-sex couples.

They will advocate for laws to secure the freedom to marry and encourage their congressional representatives to support the repeal of the Defense of Marriage Act (DOMA) which prohibits federal recognition of same-sex marriages.

Said Bloomberg: 'Mayors understand that welcoming committed gay couples to the rights and responsibilities of marriage isn't just the right thing to do.  It's also the smart thing to do for the diverse, dynamic, forward-looking cities we're all working to build.'

Menino said same-sex marriages have benefited Boston's economy.

'Cities that cultivate diversity are places where creativity and innovation thrive," he said. 'We've now had the freedom to marry in Boston for almost eight years. Since then we've seen more same-sex couples move to the city, and with that economic development, urban revitalization, and a spirit of pride and progress that are hallmarks of Boston."