2016 Presidential Nomination: Democrat Tribes
Nonetheless, there are other names mentioned.
Thus, if I had to sort the names out, I'd say there are perhaps three tribes in the field.
Clinton, Biden, and Cuomo. These have been or are office holders and would be considered pretty much mainstream of the party. As of now, only Clinton is viewed as likely to enter the race. If she were to drop out for some reason (health has been cited as a possible reason), it would be interesting to see which of these two would get in the race and whether there are some others out there we haven't even considered would enter.
Left wing/socialist Democrats
Warren who has garnered much attention from those who think President Obama has been too conservative. Sanders runs as an Independent in Vermont but sides with the Democrats in the Senate and has called himself a socialist. O'Malley served as governor of deep-blue state Maryland.
National security Democrats
Webb. Off hand, I am not sure there is anyone else in this category at this time?