Billy Shaheen is quitting the Clinton campaign after wondering out loud if Obama sold drugs as a young man.
His statement, sent by the campaign to reporters via email:
"I would like to reiterate that I deeply regret my comments yesterday and say again that they were in no way authorized by Senator Clinton or the Clinton campaign. Senator Clinton has been running a positive campaign focused on the issues that matter to America's families. She is the best qualified to be the next President of the United States because she can lead starting on day one."
Update: Clinton has apologized personally to Obama. I'm sure this is a story both candidates want to go away. Clinton probably hates that her campaign is associated with these dirty tactics, and Obama probably hates that his drug use is back in the news cycle.