> The first name that came into my mind was MLK. Rest in Peace.

We don't have to go nearly as far (or high) as MLK: Obama, GWB, Clinton, GHWB, Reagan, Carter, Ford, Nixon (iirc), Johnson, Kennedy, Eisenhower, Truman, FDR, etc etc. ...

> keeping a clean image as a politician is way harder

Biden and Obama were/have been pretty clean. It's not that hard.