Sen. Barack Obama introduced a seemingly new line in his campaign speech on Tuesday, an acknowledgment of sorts of recent criticism that his supporters have painted him as a quasi-messianic figure.
"As aware as I am of my imperfections," he told the crowd, "as clear as I am that I am not a perfect vessel, I would not be running if I did not believe that I could lead this country in a new direction, that we have a unique moment that we have to seize, but I have to tell you Houston I cannot do it by myself. No person can."
