The Citizens United case: Don't bother with a Constitutional amendment.

There is a push to restore some of the laws that were affected by the Citizens United decision. You are very naive if you think any piece of US legislation will keep corporations from attempting to influence elections. They will deal with it the same way they deal with our tax code: through the use of foreign shell companies. If you tell a billionaire who wants to spend $4 million to help a candidate that he can only spend $500,000, then he is going to start eight companies or NGO's in whatever country suits him and have them do his donating for him.

If you ban corporations from contributing to campaigns, they will hand out bonuses to trusted executives, who will then write personal checks to the candidates who will help their company succeed. Money finds a way.

What you should be worried about is how this will affect labor unions and grass roots organizations that can't relocate. When the little guy can't find the loophole, that makes the playing field even more lopsided than it was before.