Here's an interesting AP report that adds to my story on Obama and the Jesse Jacksons and Noam's piece on black pols who endorsed Clinton and today's NYT article on John Lewis announcing his intention to cast his superdelegate vote for Obama: Jesse Jackson Junior is playing a major behind-the-scenes role in bringing black pols who've endorsed Hillary over to Obama. And he's doing it by playing hardball:

One black supporter of Clinton, Rep. Emanuel Cleaver of Missouri, said he remains committed to her. "There's nothing going on right now that would cause me to" change, he said.

[snip]

In an interview, Cleaver offered a glimpse of private conversations.

He said Rep. Jesse Jackson Jr. of Illinois had recently asked him "if it comes down to the last day and you're the only superdelegate? ... Do you want to go down in history as the one to prevent a black from winning the White House?

"I told him I'd think about it," Cleaver concluded.

Jackson, an Obama supporter, confirmed the conversation, and said the dilemma may pose a career risk for some black politicians. "Many of these guys have offered their support to Mrs. Clinton, but Obama has won their districts. So you wake up without the carpet under your feet. You might find some young primary challenger placing you in a difficult position" in the future, he added.

 --Jason Zengerle