There is a difference. It's a microcosm of the difference between a god-king and an elected president.
I am also not speaking about a moral difference, I am speaking about a legal difference. How can you allow someone to spend $X on something with the logic that money equals speech but not allow someone to spend $X multiplied by a million on the same thing?
Citizens United is also terrible.
Citizens United itself was a 5-4 decision, so it's fair to say that CU was also a far-from-clear result.
The Citizens United decision rests on Corporate Personhood. Corporate Personhood was established in a case testing the limits of the 14th amendment.
Anyways, my only point was that Citizens United was not exactly a clear or obvious application of the First Amendment, and offering up the integral role of cases involving the Fourteenth Amendment as examples.
I guess merely mentioning that the decision was 5-4 would've been enough and prevented this now rather long thread.