What's Mallard raving about today?
Hillary Clinton, Barack Obama, Joe Biden.
I guess it's just to much to ask for Mallard to actually look at a picture of a person before attempting a caricature. Unless that's all part of the meta-text of this particular joke. This is actually a picture of no one in particular but we're all willing to accept that it might as well be Joe Biden.
Then again, it's possible this is as close as Mallard wants to come to commenting on Biden's ill-chosen comments regarding Barack Obama. Though that would show a level of decorum I doubt he actually possesses.
Update: Thanks to the commenter for correcting my spelling of "Barack". As I was saying to someone the other day in response to a question of what I though of Senator Obama: I refuse to pay attention until next year some time. Apparently that extends to learning how to spell his name.