I've noticed several cable dramas have cast comic actors for dramatic roles.
Spotted: Dana Gould and Simon Pegg on Mob City.
Spotted: Dave Foley and Will Sasso on Justified. (Last season had Mike O'Malley and Patton Oswalt.)
Those are just two examples, but I bet ten years ago, none of these guys would have even gotten auditions much less the part.
Things in TV have changed, man.