The Washington Post has a front page story today on how progressive groups are putting pressure on Ellen Tauscher, the chairwoman of the House New Democrat Coalition. Tauscher has made a career out of bashing the left and, until recently, has felt little pushback.

That’s about to change. Following the election, a new group called They Work for Us was formed by leaders of the labor, online and progressive organizing worlds to hold fellow Democrats accountable, through media campaigns and primary challenges.

They Work for Us was modeled after the Club for Growth on the right, which has been remarkably successful at convincing Republicans to adopt very conservative economic positions and stick to them.

Both organizations work off a simple premise: politics works based on pressure. If a Democrat, for instance, is threatened by a primary challenge from the left, they will likely become more progressive as a result. (Joe Lieberman being an exception.)

They Work For US originally chose three initial targets worthy of spotlighting: Reps. Tauscher, Henry Cuellar and Al Wynn. The group immediately heard complaints from Democratic leaders, who would rather have their allies focus on defeating Republicans.

But there’s many groups who perform that task. There’s almost no one who keeps constant pressure on Democrats to act like Democrats. It may not seem like it now, but in the end They Work for Us is doing Nancy Pelosi a favor.