What does John Edwards endorsement of Barack Obama mean with regards to the former senator's pledged delegates? Technically, the endorsement is meaningless, as pledged delegates can vote for any candidate they choose at any time. Politically, it's a different story:

[F]rom a political and practical viewpoint, pledged delegates will keep their pledge to vote for the candidate they were elected for until "released" by that candidate. By endorsing Obama, Edwards finally ended his campaign, which had been "suspended" up to now, and "released" his delegates to vote for the candidate of their choice. Of course, these delegates may decide to follow their original candidate and support Obama, and Edwards will of course be contacting them to urge them to support Obama. But until these delegates speak up and say who they will be supporting, they will essentially become uncommitted delegates. Which, essentially, makes them no different than superdelegates. (We'll keep them in the Edwards column for now).

According to Demconwatch, Edwards effectively "released" the 16 delegates he earned in Iowa, South Carolina and New Hampshire, along with an additional three state-wide delegates projected to be awarded to him at at the Iowa State Convention next month. Already, six of the eight delegates Edwards won in South Carolina and one he garnered in New Hampshire have promised to vote for Obama at the Democratic National Convention. Meanwhile, Edwards Iowa co-chair Rob Tully says he will encourage the Iowa delegates to follow their favored candidate's lead.

Superdelegates aren't holding back either. Representatives Jim McDermott, Henry Waxman, and Howard Berman all jumped on the Obama bandwagon today, along with Communication Workers of America President Larry Cohen.

Obama also picked up an endorsement from the United Steelworkers union. And the day's only half over!