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Clark Ray won't slow down your streetcars.

Former D.C. Parks and Recreation director Clark Ray has been running a balls-out campaign for the city council at-large seat held by snoozy Phil Mendelson, and yesterday released a sharply negative ad that hits Mendelson on his smart growth credentials. Ray boils smart growth down to two things: Streetcars, and vibrant neighborhoods, highlighting Mendelson’s opposition to a high-density residential development on top of the new Giant supermarket on Wisconsin Avenue.

When defending himself on these points, Mendelson talks about the need for more careful planning, which is not in itself an invalid concern. On the Giant issue specifically, his argument is that the city should be looking at changing its zoning overlays comprehensively—which it is—rather than handing out exceptions for individual projects, which sends a signal to developers that overlays around the city don’t really mean anything (Jack Evans raised similar concerns about the Follies hotel in Dupont). But I doubt Mendelson’s advocating for the overlay he helped design to be modified to allow for greater density. At that point, you have to wonder whether Mendelson is using concerns about process to avoid opposing politically popular things on their merits—and if internet polls are any indication, the Giant proposal is quite popular.

On the other hand, I’m not convinced that Ray has a great understanding of smart growth himself. At the end of the spot, he complains about Mendelson’s opposition to a bank at the site on Wisconsin Avenue—but from a Jacobean perspective, banks are totally unfriendly to vibrant streets, and Mendelson’s opposition isn’t necessarily a knock on his smart growth record (which has some other, not-insignificant achievements).

The most interesting thing about Ray’s video, though, is that the smart-growth crew has made itself into a constituency to be courted. It centers around Greater Greater Washington, where Ray clearly got much of his ammunition. But its power became clear when thousands of calls, e-mails, and tweets poured in to defend streetcars when they were threatened by Vince Gray‘s 2:00 a.m. switcharoo. That’s what political power is: When elections become about your issues, you’ve essentially won.

More on this in next week’s column!