This is how toxic the Clinton campaign is. They are joining the McCain camp to play the race card and Willie Horton her opponent.
The Willie Horton ad is well understood to have been one of the most visible examples of the use of the Republican Southern Strategy" to get working class whites to vote for them by stroking their racist tendencies and then linking their opponents to minorities. In the meantime, over the last 44 years since Richard Nixon's people developed the political strategy, its users did a great job of reviving the art of being a hidden racist. That's one of the real dangers if Hillary's Southern Strategy. The other is that John McCain will be much better at it as hidden racists instinctively understand that Republicans are the real supporters of hidden racism when the general election comes along, so Hillary's people shoot themselves in the foot, while they try to destroy Barack Obama.
See Colbert I. King "The Next Willie Horton ".
(I pointed above link to the second page of King's column. The first page was extremely short proving my thesis that thoughts dangerous to right wing interests are hidden on second and subsequent pages. The first page shows that such tricks of opponents or media-think are mostly aimed at Democratic candidates -- though Nixon shafted himself. It 's wasn't the makeup. Eisenhower's VP was a scuzz and we could tell he was. I could tell it, and I was only nine! Note that Ford's foreign policy mistake was a substantial one. McCain is making similar ones, but the news media is covering for him. Viva la tax cuts for the rich. Every time they get one they take more control over the news media and use it to control the minds of Americans.)