This has been studied for decades. There is tons of research and publications about this. There have been tons of studies done on this. 
Clarence Thomas ruled in favor of Citizens United.
Harlan Crow's political contributions then went up 862%.
Then we later find out Thomas let Crow take him on lavish trips, buy his mom's house, and help fund his wife's conservative nonprofit.
But go on about how "progressivism" is a problem...