2. First, what are these "smears"? Remember that during the primary, Bernie was continuing to run pointlessly despite being both completely unable to win and free of any party support. Democrats were probably getting pretty annoyed about bernie not dropping out like basically any other nominee would at that point. It was a pointless battle, the only thing it accomplished was to damage Clintons image and force her to spend more resources on the primary instead of the general. Bernie isn't immune to criticism.
http://www.cnn.com/2008/POLITICS/05/20/primary.wrap/