What does this even mean? It costs money to put advertisements in mass media. Either you believe everybody should be able to do that, or you believe that only some people should be able to address the public at large.
The fairness doctrine enforces two sides of view, aligning nicely with two parties. But, most issues don't have two sides. Some have three, four, or five and some have just one side. The fairness doctrine is gone because it wasn't good, not because of some conspiracy around money and speech.
I don’t know if one could even account for all the third party spending.
Money is not speech, corporations are not people.
Any one who cares about free speech would advocate for restoring the Fairness Doctrine, so we know that angle is just rhetoric.