All the blah-blah-blah about "corporations" on this thread and elsewhere is so much hooey. It's a buzz word. In the real world, commercial interests work the back rooms -- something that KD's proposal is aimed at putting the kibosh on. And they tend to play both sides of the fence. Election results are too unpredictable to risk the bottom line in the partisan game.
It's the interest groups -- chambers of commerce, unions, the anti-abortion types, the moveon.org crowd, the gun rights folks, and the like who keep CONgress and the President up at night with paranoia about their reelections. So paranoid, in fact, that they've been willing to trample the primary form of speech the First Amendment was adopted to protect, namely political speech.
Campaign Finance Reform has always been a misnomer for Incumbent Protection Reform. And now the Supremes have called "bullshit." Good for them.
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They assume an authority which is nowhere so dangerous as in the hands of those who have folly and presumption enough to fancy themselves fit to exercise it. --Adam Smith