Bill Mann at HuffPost pulls back the curtain a bit and explains one of the reasons why Rush Limbaugh over the years has been able to line up approximately 600 radio outlets to carry his show, a number the media always use to tout the talker's influence.
Answer: Limbaugh and his syndicator give the show to some stations for free. Writes Mann:
Here's how a barter deal works: To launch the show, Limbaugh's syndicator, Premiere Radio Networks -- the same folks who syndicate wingnut du jour Glen Beck -- gave Limbaugh's three hours away -- that's right, no cash -- to local radio stations, mostly in medium and smaller markets, back in the early 1990's.
So, a local talk station got Rush's show for zilch. In exchange, Premiere took for itself much of the local station's available advertising time (roughly 15 minutes an hour) and packed the show with national ads it had already pre-sold.
Think Gold Bond Medicated Powder.