Don’t confuse the Fairness Doctrine with Equal Time. The Fairness Doctrine required broadcast TV and radio to provide “fair” coverage to controversial issues. In practice, it encouraged stations to avoid giving any in-depth coverage to controversial issues.
Equal Time means that a station has to provide the same access to all candidates for a given office for a period of 60 days before an election. If Congressman Smith buys $10,000 of commercial time on his local TV station, that station has to give Smith’s opponent the same opportunity to buy commercial time (that’s why here in the wing states, you’ll see McCain and Obama commercials running during the same commercial breaks.) If the station provides free time for Congressman Smith, it has to offer Smith’s opponent free time.
Another provision of Equal Time is that if stations sell time to political candidates they must charge only “the lowest unit rate” for that time. That means a politician who only has enough money to buy a single commercial would pay the same as an advertiser who had negotiated a million dollar contract.
Because of that, a lot of stations hate political advertising. Not only do they have to sell it cheap, but if they sell out their commercial slots, they have to bump higher-paying non-political advertising to make time for Smith and his opponents.