Complex sentence: McBroom's uncle Victor led his brothers in running the corrupt city of Kankakee's patronage racket out of their Cadillac dealership, exercising power through the local Republican party for 70 years.
Split into simpler sentences: McBroom's uncle Victor led his brothers in running the corrupt city of Kankakee's patronage racket. The family worked from their Cadillac dealership, exercising their political power through the local Republican party for 70 years.