> Peel it back even more: how does any State not fall victim to monied interests?

Go with either the FDR route (94% tax rate), or the CCP route (clip the wings of the Icaruses who fly too high).

Edit: if the above are too extreme, another approach would be firm and consistent application of anti-competitive laws, resurrecting the fairness doctrine, and stop pretending that artificial constructs have human rights.