RINOs at the federal level, and in state Florida Democrats.
Redistricting was initiated by the Dems in Florida.The GOP did not fight it as they could have.
Republicans had FULL control of redistricting in Florida this past cycle (2011). Democrats probably didn't even support the redistricting plan, because overall it created more Republican districts, and they surely had nothing to do with thinking of it. It was the squishy liberal wing of the FL GOP who took down West, not the Democrats.
The squishes targeted not only Allen West for extinction but successfully disposed of another conservative Rep (Sandy Adams) by putting her into the same district with an old bull moderate and the moderate won the primary, as they hoped would happen.