It took an awfully long time. But John Edwards finally came out for Obama just as Hillary Clinton's big win in West Virginia was adding a little oomph to her implied argument that racism among white, working class voters means Democrats can ill afford an Obama candidacy.

Actually, it might be that very line of argument that pushed Edwards into the Obama camp. Clearly, John and Elizabeth liked Hillary's health care plan better. Edwards chastised both Hillary and Obama for their fundraising from industry (although Obama will make much of his and Edwards's shared anti-PAC stance). Edwards can hardly fault Hillary too heavily for voting for the Iraq war, since he cast the same vote, only to apologize later.

The recurring Clinton race-baiting in the South, though, no doubt pushed Edwards's buttons. As a product of the segregated South, Edwards has spoken movingly about being shaped by the Civil Rights era, and the need to overcome exactly the kind of bigotry Hillary Clinton is now peddling.

Not that that's the whole story. Coming out for Obama this late shows less enthusiasm for the candidate than sheer practicality. Obama, it would appear to nearly everyone, is going to be the nominee. If Edwards wants to be get on board the train before it pulls out of the station, he doesn't have much time left.

An earlier endorsement, and some enthusiastic campaigning in Pennsylvania by the author of the "two Americas" speech, might have helped temper the problems Obama is having, and Hillary is exploiting, with white, lower-income voters who don't seem to trust him.

Still, the Edwards endorsement was timed to knock Hillary's West Virginia victory out of the news, and may yet make a difference to some voters, to the extent that endorsements ever do.

Between the endorsements of Edwards, Richardson, the slowly turning tide of superdelegates, and, on the same day as the Edwards endorsement, the pro-choice group NARAL, it seems clear that just about everyone in the Democratic Party, with the possible exception of Hillary, knows that this thing is over.