The fact is that Republicans have been in control of all legislation in Congress for the past four years; the Democrats have had no power to move legislation. Yes, they can propose legislation, but only the Republican chairman of any committee can move that legislation out onto the floor where it can be voted upon.
So, it does lobbyists no good at all to try to bribe Democrats; Democrats have NO POWER.
Remember: It is not illegal to take lobbyists' money. It is not illegal to take money from the Indian tribes. What is illegal is to take that money based on a promise to do something in return for it.
The Republicans, along with their media puppets, are going to do everything they can to portray this as "equally" a Democratic scandal -- it is NOT. It is wholly a Republican scandal.