Is there an answer? I'm not sure. I suppose the short response is that you worry about condescending to Muslims when you are running for office in a Muslim country, you worry about condescending to Pennsylvanians when you are running in Pennsylvania. But it's not really an answer; 1) Nobody likes to be condescended to, and nobody's likely to be convinced when they feel belittled; and 2) in my view of the world, at least, condescension--social inequality--is a grave political sin in itself whenever it's practiced.
Some other obvious potential ways out come to mind, though they make me sound like a tenth grade civics teacher (or Andrew Sullivan):
1) Always entertain the possibility that you might be wrong and those whose "superstructural" behavior you are explaining are right. Call it the "Marxism of Doubt"! The left ignored this rule when it declared opposition to welfare one of those "scapegoating" behaviors that would thankfully disappear when Democrats delivered good jobs and good wages. In fact, opposition to welfare was fairly constant through good times and bad--perhaps because the opponents of welfare were right (as I think they were). In any case, they won.
Obama ignores this rule when he dismisses opposition to affirmative action and trade and illegal immigration as similar "scapegoating" behavior. Mighty convenient to say that the doomed "superstructure" happens to include all the beliefs you disagree with.
2) Don't pick fights unnecessarily: Do Democrats have to scorn people who cling to God, whatever the reason? No. Do they have to scorn people who cling to guns? Maybe, if Democrats really think they have to believe in gun control to be Democrats. But in fact they've caved on gun control--deciding, in essence, it's not a core position. Maybe they'll soon decide that race-based preferences and legalization of illegal aliens aren't core positions either--perhaps because, heeding Rule 1, they've been convinced by the people they are condescending to. (Obama is clearly a ways away from that moment.)
3) Emphasize the common goal: A companion to rule 2. If Obama thinks Pennsylvanians will stop clinging to God and guns and ethnic prejudices once they have a real prospect of getting national health insurance--well, talk about national health insurance! Let the prejudice take care of itself (if you really think that's what's going to happen).
4) Where you have to disagree, have the respect to do it forthrightly: A modern national Democrat, contemplating religious small town Pennsylvanians, won't want to concede, say, that homosexuality is immoral. Westerners, contemplating the Muslim world, won't want to tolerate stoning adulterers or honor killings, certainly not among Muslim immigrants to the West but not in the East either. Free speech and inquiry aren't things we think Chinese Communists might be right about. In these cases, the only thing to do is to honestly say "Yes, we think you are wrong and that you'll eventually come around."
I'm not sure rules like this really dispel the stench of condescension. Rule #3 seems like a PR gambit--hiding what you really think, maybe by keeping troublesome bloggers out of your San Francisco fundraisers. And even #4, don't the Chinese know we think we're not only "right" on a specific issue but "better" in some sense--more advanced, further along on the arc of history? I don't know that it helps if they feel the same way about us.
If anyone has the answer-even Charlie Rose!--I'm all ears. 2:44 A.M. link