This, and any other revelation involving a Democrat, a Republican, or an Independent politician, does not surprise me in the slightest.
I think it's fair to say that most of the congresscritters - particularly those who have been around for a couple-three elections or so - are going to be tainted in this way or another if exposed to even a modicum of scrutiny.
The temptation is too great and the selfishness is too rampant.
Congressional ethics laws, policies, and mandates are a joke.
Term limits, anyone? At least in that sense, the critters have to develop the expected arrogance, narcissism, and selfishiness before actually acting on it.