An interesting idea. One which I am not completely opposed to, however, I am slow to endorse anything requiring private firms to do any particular thing, especially when it involves government and money. Now, you say it would be "free air time", that air time costs money. If the candidates don't pay for it, and the government doesn't pay for it, the stations/networks would have to pay for it. Even if that were only in lost advertisement revenue.I personally think that the State-Controlled airwaves should be made available free of charge to anyone with demonstrated support during the biannual elections for federal office. By that I mean that the radio and television stations that are licensed by the FCC should be required to run candidate-produced advertisements on a 1:1 ratio.
What I didn’t say was that there would be time limits; say from September 1 to Election day. This would be once every 2 years. And remember, they can buy whatever they want on top of what they get for free so it’s not as if the stations would be making nothing off of the election.