Watching the reaction of most republican-supporters today, I'm seeing a pattern I've seen with other forms of privilege (eg, sexual harassment, white people having little experience with "bad cops" etc).
Romney dismisses 47% of the country as freeloaders on the basis that they pay no federal income taxes.
Lots of Romney supporters who paid no taxes last year (or anti-Obamas) respond with "Hell YEAH!" because they hate those freeloaders he's talking about.
They KNOW they aren't the kind of moochers that Romney is talking about. They worked hard/paid SS and medicare all their lives/served in the military/ARE serving in the military/paid for disability insurance/are doing the hard work of raising kids supported by alimony/are students/etc etc etc. All the things we know are perfectly good reasons why you may not be paying taxes this year.
He CAN NOT be meaning US. WE are not the nasty freeloaders that we all hate.
This is why this revelation will, if anything, strengthen his base of folks who vote against their self-interest. They believe that they're hard working folks (even if they no longer work) who deserve everything they've got. They are willfully blind to all the government assistance in the same way that I, as a white, large, middle class male have never had anything but polite encounters with police who came only when I called them or did something dumb like speeding in front of them, and I've never been harassed or stalked like my wife has just for walking down the street with long hair. They don't see the government any more than I see most of the racism and sexual harassment. They may even understand it intellectually, but it isn't "real" at the gut level unless something really rubs it in their face, usually a tragedy that happens to someone close to them, or maybe to them.
Romney's foreign policy fiasco last week and his 47% revelation this week won't alienate many voters who are already in his camp. Some may even see what's going on, but still vote against Obama. (I've seen some Redstate comments like this from actually poor people who work hard and pay no taxes)
We can only hope though, that his comments harden the Democrat base too, bring some independents over, sway the last few % of undecided. I don't see how his behavior could really help him.
But it might not hurt him either. Privilege is powerful. People who are buying the current Republican party line believe that they are tough individualists who earned everything they got, whether or not they got it from the government. Everything Romney does or says is going to be filtered through that prism.