The Wisconsin exit polls are bad news for Clinton if this is a sign of things to come, as Obama continued to make progress among several key demographic groups. Clinton’s strategy in Ohio and Texas is based on winning working class white voters and women, but Obama won whites 52-46, those without a college degree 54-45, and those with an income of less than $50,000 by 53-46. Among women, Clinton’s edge was just 51-48. He also won among every age group other than those over 60. As far as I can tell, Clinton’s base has now narrowed to elderly white women.