When the Jaguars covered almost 10,000 seats in 2005, they received a lot of flak, critics said it was a sign that Jacksonville couldn't support an NFL team and as it turns out, the Jaguars were just ahead of the curve. Covering seats — or at least shrinking the number needed to avoid a television blackout — is now on the verge of becoming a league policy. The owners will vote June 21 on a proposal to allow teams to shrink their blackout number by 15 percent. The teams would have to announce their blackout number in July, but, unlike the Jaguars in past years, they could sell those tickets taken away from the blackout manifest if there were a demand for them. It is uncertain how many teams will take advantage of the new policy, it wouldn't affect the teams that traditionally sell out all their games. Source: The Florida Times-Union
85% tickets sold is reasonable, especially since club seats are already excluded. You figure a stadium of 65k would meet that mark at a little more than 55k. Even with a sluggish economy most if not all teams could meet that.