The solution is reversing Citizen's United, when the Supreme Court held 5-4 that campaign contributions represented "freedom of speech" and could not be limited. In a literal sense, Citizen's United enshrined the idea that your voice (and vote) are proportional to the amount of money you can bring to bear.

One of the lessons I've taken from this case and others related to gerrymandering and voter suppression, for instance, is how deeply the integrity our democracy depends on tactical execution of the broader ideals at stake. It's our ability to handle issues at the margin that will determine whether the whole thing works or falls apart.