i'd be more in favor of taking campaign funding out of individual's and corporation's hands altogether, and lettting the fed gov't provide a limited amount for each party candidate, period.
if people want to contribute money it can go to the political party they choose, and not any particular candidate directly.
That would change a lot more about our political system than you seem to realize. At present, every candidacy more or less goes it alone, it's an entrepreneurial model, the parties are merely brand-labels. No elected official owes any obedience to his party organization as such. Putting the parties in charge of distributing campaign funds would give the party officials, as distinct from the government/elected officials, a lot more power than they have now, might even eventually transform American political parties into European-style cadre parties, with membership cards and membership dues and mechanisms for expulsion from the party. Not that that's necessarily a bad thing.