Obama has decided that the best form of defence is offence and is ripping into Hillary Clinton in highly personal terms for her attempt to make political capital out of his comments about small town mid-Westerners clinging to their faith and guns in an uncertain world. The tactic of decrying all criticism of him as politics as usual works when up against someone like Hillary Clinton, who is seen by so many voters as a say anything, do anything politician. Whether it will be so effective in a general election campaign against John McCain is quite another question.
There’s no doubt that Obama’s words have hurt him politically; the fact that they were said to a bunch of wealthy San Franciscans makes it nigh-on-impossible for him to put a positive spin on them. Obama has given himself both a major problem for the Pennsylvania primary and the general election by further alienating the white working class voters he is already having such trouble winning over.