Climbers For Kerry, a Seattle-based group supporting presidential hopeful John Kerry, is launching an unusual PR stunt — a three-week effort to “take back” North America. Specifically, the North America Wall on El Capitan. The organization’s goal is to send a steady stream of climbers through the black, North America-shaped diorite patch in the center of El Cap’s southeast face, equipped with “highly visible” Take Back North America T-shirts and “haul bag decorations” that may be seen from El Cap Meadow. (Climbers For Kerry will similarly equip climbers attempting other one-day or longer routes in the Valley from Sept. 11 to Oct. 2.) Organizers will temporarily fix five crucial pitons on the NA Wall to prevent damage to the route; the 1964 route goes at about C3 with a few key fixed pieces. To sign up for a climb or learn more about this event, including slideshows and a “Beat the Bushes” trash cleanup, go to www.climbersforkerry.com.