That or they have had their lives and those of their family and friends threatened. Only reason I can think of that also explains bowing down to the Muslim nutbags of the world.
Probably a combination of things. The dems accepted the bribe so then they were in bed with the cartels/mafia. If they had any second thoughts after accepting the money they were threatened with the death of all their family members so now they stuck. If they quit they and their families will die so they have to stay the course to destroy America. They are in it up to their noses.
A better solution is to destroy the cartels/mafia but that would take political will few besides our good President has.