It's clear that special interests and their lobbyists spend enormous sums of money to back political candidates, both elected and seeking election, with the expectation of quid pro quo when the candidate introduces or votes on legislation of interest to the lobby. In many cases the lobby writes the legislation.
I many developed countries this would be called what it really is...bribery and corruption. In the USA it is called 'doing business'.
This petition calls on the President to use an executive order to bar both congressional candidates and current members of Congress from accepting donations from any source except individual citizens, the amount to be limited to $100 per citizen per year.