I honestly can't think of a reason someone would vote for Blanche Lincoln. It can't be electability, because she's roughly as popular as smegma, and it can't be her policies, because she's not moderate on any of the right issues. I could understand not supporting Halter, but actively supporting Lincoln is beyond my comprehension.
There's still a significant portion of Arkansas Democrats who like her on a personal level (like the family of a friend of mine who lives in AR), and she's done a good job providing agricultural pork as well.