From Jonathan Singer at MyDD here (there's a video).
The Club for Growth has been one of the most successful entities in the nation in electing Democrats to Congress. Whether it was helping force Bill Sali (Idaho) and Tim Walberg (Michigan) through GOP primaries in 2006, only to see both lose reelection bids in 2008; unsuccessfully primarying Linc Chafee (Rhode Island) in 2006, weakening him for the general election (which he eventually lost); pushing Andy Harris (Maryland) and Steve Pearce (New Mexico) through primaries against moderates into general elections they ended up losing in 2008; or, most recently, forcing Dede Scozzafava out in the special election in New York this week, easing the Democrats' path to victory, the Club has been remarkably effective at helping Democrats win elections.
Now that the Club is turning its sights on Charlie Crist, Florida's moderate Governor and GOP Senate aspirant, the real question is (as I asked on Twitter yesterday) just how long does Crist stay in the GOP primary before jumping ship to run as an Independent or even a Democrat (a la Arlen Specter)?
See here too (via The Advocate).