What I've found amusing is that there's a large, completely bubble dwelling portion of the Republican power structure that thinks this is a winning argument. Your Erick Ericksons, average Corner poster, and apparently Mary Matalin... I thought she was smarter but living in DC for 20 years will do that to you I guess.
I don't think it's DC; so far most of the DC types (Noonan, Brooks, Scarborough, etc) have denounced the comments. The only people suggesting this is a winner are on the far right, like Erickson and Drudge. I must say I was surprised that Matalin seemed excited about this. That's not to say she is normally sane because she isn't, but she tends to recognize a loser when she sees it. Just a couple months ago she could barely defend Romney's campaign, it's hard to see what has changed to make anyone excited about his prospects.
I'd say most people don't like seeing their neighbors demeaned. The problem here isn't just about demeaning democrats, he literally said half the country is dependent on government, don't want to work, and they're all voting for Obama. I honestly think he might have been able to get away with saying 20% of the country is dependent, because that would have clear racial connotations and I doubt Obama wants to have a discussion about race (see: how potent the welfare ads have been for Romney.
But 47% of the country includes a whole lot of white people too. From soldiers who don't pay income taxes while deployed to old people to children of the working poor. I don't think common sense folks will take kindly to a presidential candidate literally saying "fuck half the country."
btw, the video has over 2 million views already