Some folks have reported some nasty push polling in Iowa against Dean. Vile questions, along the lines of how McCain was smeared in South Carolina last cycle:

"Would your support for Howard Dean change if you knew that he performed abortions while working with Planned Parenthood?"

"Would your support for Howard Dean change if you knew about his history of spousal abuse?"

ABC suggests that it was Kerry, but it's all based on rumor -- nothing substantiated yet as far as I can tell. If it was any Democrat they should be (the political equivalent of) excommunicated from the party.