Senators cannot be impeached.
Dingy needs to be Censured then Expelled. He’d likely resign before facing Expulsion. All the better. It takes 2/3 of the Senate, I believe.
That may happen is Repubs win the Senate, but on the other hand here are so many RINOs in the GOP today it isn’t funny, like my brother says: Today we have two partys: Democrats and Democrats lite.