From CBS Chicago:

The President of the South Suburban Branch of the NAACP alleges a director of the re-election campaign of Barack Obama has threatened and intimidated him because he doesn’t support the president.
..
David Lowery says he believes he was threatened during a phone conversation with Louis Raymond, the Illinois political director for Obama for America.
Lowery says he doesn’t personally support the president because he’s not addressing issues important to the black community. He said he was explaining that to Raymond when the Obama campaign official told him, “You know what? I know everything about you.”
Lowery says Raymond added, “We’ve been watching you, and since you don’t support Obama, we’ll deal with you,” before hanging up.
Lowery filed a report with the Oak Forest police report, he says, “in case something happens.”

The Obama campaign issued a statement saying, “Unfortunately there seems to have been a miscommunication regarding this conversation and we have since discussed with the campaign staffer in an effort to clarify the matter.”