No other presidential candidate, no matter his or her polarizing positions, has felt it necessary to seek protection from the Secret Service.

 But last week we learned that Obama has sought and will receive that protection, the only candidate ever to do so this early in the process. Only one other candidate even has a Secret Service detail: Hillary Clinton. And that's because she's a former first lady.

 You know who else required early protection? Jesse Jackson, when he ran for president in '84 and '88.

 Neither Obama's campaign nor the Secret Service will comment on precisely what went into the decision to assign a detail to the senator, beyond saying it was based on no one specific threat.

 But one need not be a seer to divine the reason. Put it this way: The darker the candidate's skin and the more serious his candidacy, the earlier he seems to need protecting.