General Discussion
In reply to the discussion: Obama ENDORSES Bernie Sanders’ Constitutional Amendment to OVERTURN CITIZENS UNITED [View all]Nye Bevan
(25,406 posts)and Citizens United did not affect that ban.
The case did not involve the federal ban on direct contributions from corporations or unions to candidate campaigns or political parties, which remain illegal in races for federal office.
http://en.wikipedia.org/wiki/Citizens_united#cite_note-Carney2010-4
As for a Constitutional Amendment, something like the following would work:
The prohibition in the First Amendment to this constitution against Congress making a law abridging the freedom of speech, or of the press, shall not apply to speech relating to candidates in Federal elections within the 90 day period prior to such elections.
Arguably the "or of the press" could be removed here, but then I think there's a big loophole opened that a lot of entities would try to become "the press".
Personally I don't like this solution and prefer the route of full disclosure advocated by the ACLU.