In non-Presidential elections the candidate who raises and spends the most money wins well over 90% of the time. Issues take a back seat. (Presidential elections are different because there is a lot of free press). And through PACs the wealthy can give as much money as they want. In today's America it is all about name recognition and marketing.
So of COURSE people like the Koch brothers and Soros have immensely more power than the average American. Politicians trip all over themselves to kiss their asses. It isn't even subtle.