I think the club announced when we played Man Utd that we could've sold "twice the number" of tickets sold for that game. That might just have been a standard thing to say in the circumstances or a way of saying demand outstripped supply a bit, but this part of the country is definitely an "up for the cup" type football area, interested in the occasional big/knockout game rather than being yer week in, week out sorts.
We did actually sell 42,000 tickets for a game v Walsall about 8 years ago, let us not forget.