whispering campaign

whispering campaign
    n 1: the organized dissemination of derogatory rumors designed
         to discredit a candidate
    

28 Moby Thesaurus words for "whispering campaign":
      aspersion, character assassination, dirt, dirty politics,
      gossip column, imputation, innuendo, insinuation, juicy morsel,
      last-minute lie, malicious gossip, muckraking, mudslinging,
      mudslinging campaign, personal remark, personality,
      political canard, reflection, roorback, scandal, scandalmongering,
      slander, slur, sly suggestion, smear campaign, suggestion, tidbit,
      uncomplimentary remark