The Supreme Court overturned precedent about granting "political speech" to corporations, unions, and other organizations, "Justices Overturn Key Campaign Limits", New York Times, 2010-01-21.
I find it very interesting that the "conservatives" who were appointed by presidents from a party that proclaims it is for individual liberty gives greater liberty to corporate interests.
We can't do much about various groups promoting or panning candidates, especially candidates for whom few of the members of the group can vote. But we can refuse to vote for candidates who accept contributions from groups or from people who have no right to vote for that candidate. And we can let them know why we won't vote for them.
Too often we as a people make voting an either/or proposition; we must vote for one of the major party candidates or we will be "throwing our vote away". It is way past time to stand up and be counted in a different way.
If any candidate for whom you might vote accepts contributions from those who can't vote for him or her, write and tell that candidate that you will vote for somebody else or leave that spot on the ballot blank. Maybe you will make no difference for an election cycle or two, but we have to start someplace. If you tell your friends and relatives what you did, if you write letters to the editor about what you did, maybe, just maybe the idea will catch on.
If you vote for the same old, same old, is it really democracy? Real democracy starts with individuals making their voices heard, not with sheep following the herd.