Obama's breakthrough among whites

A historical perspective from William Saletan, with a few, very important stats:

It was possible to argue, as Clinton implicitly did, that Obama's ceiling, like Jackson's, was limited. Obama hadn't cracked 40 percent of the white vote anywhere. He hadn't even cracked 37 percent. Pundits theorized that John Edwards' presence in South Carolina helped Obama by splitting white support that would otherwise go to Hillary Clinton. The theory implied that in a two-person contest, Obama still wouldn't draw much white support.

Tonight's results crushed that argument. Even if you don't count Obama's caucus victories in Alaska, Colorado, Idaho, Kansas, Minnesota, and North Dakota, he shattered his previous white-vote ceiling in 11 other states. In eight states, he crossed the 40 percent threshold. In Connecticut, he tied Clinton among whites. In California, he beat her. In Utah and Illinois, he won commanding majorities.

I don't mean to oversell what Obama accomplished tonight. It's easier to ascend from the 20 percents to the 40 percents when you've got only one opponent left. It's easier to climb from 30 percent to 40 percent than from 40 percent to 50 percent. And it's easier to win support from white Democrats than from white Republicans. But when you look at Obama's numbers tonight and compare them to Jackson's numbers 20 years ago, you're looking at a sea change. This is not a diversity-training exercise. It's a nationwide primary to choose the next president of the United States. The American color barrier, at its highest level, is collapsing.

That's been a central theme of Obama's campaign all along. The message of South Carolina, he suggested in his speech tonight, was that "maybe we don't have to be divided by race and region and gender." But that message didn't come from South Carolina. It came from California, Arizona, Connecticut, and the other states that voted Tuesday. And with those votes, an aspiration is becoming a reality. No matter whom you support for president, that's a victory worth celebrating.