The major problem of politics is that no matter how clean you paint it, the deeper part would remain dirty. So many elections come and go with little pronounced vices . However, when you look deep into the election process you will see several shady areas where many things have been done to secure the victory.
Politics moves side by side to reach and enhance a certain group of people, when that happens some part of the society begin to face tough times, while the rulling set of people would be making solid profits and wealths. Whenever anybody gets to the point where their side is the winning party, the definition they all give to politics would change. It then become what they see it as. Nothing is with politics it's about the people and power.
I am a little bit in disagreement with your idea about politics that everyone participating is a bad person, I don’t think so I instead also know that the number of those practicing politics recently have increased and it consists of both the good and the bad people. I know that if you want to build influence around your self and your people