Hillary Clinton's campaign has, to a large degree, come down to arguing that she would be a stronger general election candidate against McCain, especially because of her strength among white working-class voters.
Two interesting looks at that argument:
Yesterday's national Quinnipiac poll, as first noted at TPM, blows up some of Clinton's most popular talking points. Not only do Obama and Clinton beat McCain by similar top-line numbers -- 47-40 and 46-41 -- but they perform almost identically among non-college-educated whites. McCain bests Hillary 48-41 in that group, and bests Obama 46-39.
That suggests two things: That a lot of Hillary's blue-collar support comes from people who prefer McCain to either of the Democrats, and that her big advantage in that demographic group in some regions (such as Appalachia) is balanced by better Obama performance with the same voters in other regions (such as the upper Midwest). And there is support for the idea that Hillary would do better against McCain among blue-collar whites in some key swing states.
Other interesting results: Clinton argues that she is stronger among Catholics -- but the poll found McCain beat Clinton 49-41 and beat Obama 46-37 among Catholics. Clinton also argues that she is stronger in swing states. The poll, however, found that the two Dems fared similarly in "purple" states, both besting McCain -- Obama by 48-39, Clinton by 49-38.
The big difference between the candidates? Obama, as polls have consistently shown, loses more Clinton Democrats to McCain (57-24), while a larger proportion of Obama supporters would stick with Hillary (69-15). The result of this is that Clinton does better among Democrats (80-11) than Obama (75-13). But Obama makes it up among independents -- besting McCain 48-37, while Clinton ties 41-41.
Elsewhere, the Washington Post looks at the who's stronger question through the lens of the electoral college. The answer, by a slight margin, is Clinton because she is stronger in three swing states with 68 EVs (Florida, Ohio, Penn.) while Obama is strong in six states (Colorado, Iowa, Minnesota, Oregon, Virginia and Washington) with 57 EVs:
"She is stronger -- although not by much -- if the playing field in 2008 is a mirror image of the battlegrounds of 2004 and 2000....But that argument only holds if you believe two things: First, that the playing field will be essentially unchanged between 2000/2004 and 2008 and, second, that current polling is an accurate predictor of what things will look like in November."
Both ways of looking at it, the differences seem too slight, and the advantages to one or the other too marginal, to persuade some massive number of superdelegates to go against the grain for Clinton...