The Citizens United ruling had essentially noting to do with "money in politics" and was just a bog standard first amendment ruling against a federal agency attempting to read the power to regulate political speech into a statute that had been passed a mere eight years earlier.
Contrary to the misinformation spread through the media, the court did not rule that "money is speech", but ruled almost exactly the opposite: it was the FEC that was attempting to argue that "speech is money" -- that using resources to speak in a way that might persuade voters was equivalent to donating those resources directly to a candidate -- and therefore they had the right to restrict the publication of "electioneering communications". The court ruled that no, speech is not money, and is protected by the first amendment under all circumstances.
So the ruling put things back the way they were in 1995, before the FEC had ever gotten the idea that they had the power to censor speech.