As I said, you don't get to have it both ways and pick and choose. You are the one insisting it's the constitutional process that is supreme, so you get to take Citizens United vs. FEC, together with Roe vs. Wade, DC vs. Heller, National Federation of Independent Business v. Sebelius, etc.
They all are equally constitutional.
Don't like it - blame the founding fathers and those after them who haven't made the political system to your likeness. Or stop loosing elections.
Alternatively if you wanted your opinion on the constitutionality of something to really count you should've gone to Harvard or Yale law school, be really good at politics and you could've been one of the 9 people whose votes count. But you didn't do that and that is nobody else's fault.