Photo by omarali.md.

Twenty-four landmarks in the District, Maryland, and Virginia are competing for online votes in hopes of landing up to $1 million in grant money to fix themselves up. Sixth and I Historic Synagogue, for instance, is hoping to refurbish its stained-glass windows, while the Greenbelt Theatre is looking for the funds to restore its ornate lobby.

All fans of these buildings need to do is vote or tweet their support. The contest, which is sponsored by the National Trust for Historic Preservation and American Express, is an annual event that pits a group of historic sites in a city or metropolitan area against each other to determine which one can get the most public favor for a repair job. And this year, the contest is settling on the nation’s capital region.

Between today and May 10, people can lend their support for a place by voting on the contest’s website, posting an Instagram photo of their preferred location, checking in on Foursquare, or simply posting on Twitter. For instance, if one wants to help the Congressional Cemetery in its bid for a grant to patch up the roof on its mausoleum vault, all one needs to do is visit the graveyard or, barring that, send out a favorable tweet (With the requisite hashtag, of course.) Locations are awarded points based on how much social juice they can muster.

The winning site does not get the full $1 million, but it is guaranteed its whole grant request.

Other sites in the running include Georgetown University’s Heyden Observatory, the Marine Corps War Memorial, Meridian Hill Park, and Tivoli Square. But the clear frontrunner is the Washington National Cathedral, which is looking for some cash to repair its nave vaulting. It’s only the first day of voting, and the cathedral already has 22,500 points, well ahead of the 6,750 accumulated by Sixth and I.