A person that is seeking to be elected to a federal office and currently on the ballot for such office may only accept money donations or anything else of value from voters currently and legally registered to vote for the office the person is seeking.
No person currently holding a federal elected office may seek a different federal office without resigning from their current federal office.
This would stop most lobbying, it would stop people like Hillary Clinton, George Soros and other NGA's from interfering (with money) in elections they have no business sticking their nose's in, it would make those elected go home to promote themselves to their voters, it would result in more people registering to vote because they would have a real say-so in what their representative was doing because the elected person would have to listen to them, it would do away with any more Chinese money getting into elections. Something like this would make people like John McCain less powerful since they would not have as much power anymore to act as if being a Senator from one state means he has a national office.
None of this will happen but it would be nice if we could get back to the founders idea of a representative republic. Allowing these bozos in Washington to only get cash from their own voters would get us closer to that.
Some of the kinks would need to be worked out - but you've come up with a GREAT idea.
"We need one simple campaign finance law. One that I'd bet the founders would have put in the Constitution if they saw all the stuff going on today."
Our founders couldn't have suspected it would come to this because they never intended for anyone to make a career out of poilitcs. Most of them had farms or other businesses back home, real jobs.