For Obama, this spring’s fights over class represent both a political challenge and a definitional moment. His most consistent argument — that higher taxes on the well-to-do are the essential element in preserving popular government benefits to the middle-class and poor — is in tension with his most consistent promise, that his presidency will break Washington gridlock and elevate problem-solving over ideological purity…

On the other hand, Obama’s dependence on class-based politics shows how far the country has moved from the politics of a generation ago. In Bill Clinton’s presidency, he and centrist political advisers like the pollster Mark Penn concluded that any appeal that smacked of class warfare was a loser for Democrats. Their belief was that even most swing voters who weren’t rich wanted to be, or at least didn’t resent those who were, and wanted Democrats to preach a message of unity and bipartisan progress…

“Whichever party is the voice of the middle class ends up winning presidential elections,” said Ayres. “When Republicans were winning five of six presidential elections we were the voice of the middle class and Democrats were the voice of special interests and minorities. And just as Reagan pinned the tag of special interests and minorities on Democrats, Obama pinned on us the party of the rich this time. And then we did what Democrats did in the 1980s — we played into the caricature.”…

“These are people who need the $80 to $100 you get to spend two hours at a focus group,” said the pollster. “I remember one woman saying [of Ann Romney’s line]: ‘We struggled so hard we had to cash in some of our stock shares — how am I supposed to relate to that?’”