The Big O*
If the anecdotes and exit polls are correct, Barack Obama has solved the Clinton calculus and is starting to make headway into her base. This should make Mark Penn shiver.
From the New York Times: Mr. Obama’s strength crossed a range of demographic groups, as he gleaned majority support from voters regardless of age, income and education. He was backed by independents and Democrats, liberals, moderates and conservatives.
Another point in Obama's favor is that he appears to have taken a few independent voters who might otherwise have crossed over to help John McCain.
An object in motion tends to stay in motion.
*O-lectible: Morning reports of yesterday's Potomac/Chesapeake primaries confirm Obama did indeed cut heavily into Clinton's base, making big gains with women and Latinos. Whether or not this carries over to states like Texas and Ohio remains to be seen, but at this point the nomination is Obama's to lose.