2 does not a comprehensive study make.
Rush is making money for stations all over this country, red and blue states alike.
If they can't sell the product, that is a sales department problem. Businesses like money and audiences for their advertising, Rush provides that everywhere he is.
I never said this was a comprehensive study, those are your words. However, it does show what we here in the first state call "The Delaware Way". People in "lower slower Delaware", the bottom two counties have a different approach to things, including politics, very Red Counties. If you saw the You Tube video about a town hall meeting Delaware's lone Congressman, Mike Castle, had about 5-6 weeks ago in, I believe it was Bridgeville Delaware, you saw some real wacked out ULTRA right wing Republicans who looked and sounded just as crazy as the videos that Fox News played of Reverend Wright's congregation back during the election. These folks appear to not be very educated. These folks make up a large part of the Republican party in Lower Delaware, where most of Delaware's Republicans live. Those folks make up a large part of Rush's listeners downstate where that station sells Rush's local avails very well. Compare that to a very different audience from the highly educated (many PhD's in Chemistry, Engineering, Medical Science, Electronics, etc), who tend to be far more moderate leaning left, more often than not, Democrat. These folks are not the main body of Rush's listeners generally speaking. My point is, even though Delaware is very small (approx 100 miles in length) the lower two counties are like a seperate state when compared to the Wilmington metro area. Those folks from downstate see the world very differently as they live in a more rural environment, etc from those of us from the more urban/metropolitan lifestyle of Wilmington.
That doesn't mean Rush's show won't make money for all blue county stations, but it could be a factor in those that are not doing as well. Sales people legally aren't allowed to hold a gun to the customers head to get them to buy local avails on Rush's show, so if a business or a group of businesses are NOT comfortable having their name associated with Rush or his show, then even the famous salesman of the 50's-60's for Parade Magazine who won all sorts of awards for being such a great salesperson, Red Motley, would not be able to sell that air time.
Remember the big uproar when Florida Orange Juice bought network spots on Limbaugh's show? They actually lost business, as I recall. People nationwide got upset and complained to Florida Orangejuice threatening boycotts, etc. The OJ folks dropped their ads from Rush's show in very short order. There was the big uproar when Rush himself did a Pizza Hut TV commerical for the cheese stuffed crust pizza. The ad got pulled very quickly. So there is some precident for what I'm saying. Liberals don't like Rush and apparently will complain to the companies demanding they not sponsor Rush's show or use him as their spokesperson. My guess is, (again note the magic words) that you'll never hear Levi Strauss Jeans or Ben and Jerry's Ice Cream advertising on Rush's show as those are very liberal companies, yet it wouldn't surprise me to see their spots on MSNBC's Keith Oberman's show (they may be on MSNBC, but I don't watch Oberman's show so I wouldn't know for sure). Businesses spend big time money NOT to upset people, but to get people to like their company and create a desire to buy whatever their company is selling. They're only going to buy time either as a network spot or a local spot on Limbaugh's show if they believe it will be good for their business, or if their company is a conservative oriented company and they are trying to say, hey we're one of you, buy our stuff. Of course such a company probably would not buy time on Keith Oberman's show for the same reasons. So it's not a slam against Limbaugh anymore than it's a slam against Oberman.