In my mind, I tend to think that the answer is fairly clear cut in that Gatsby is much more tragic than Daisy is. Even if one were to view Daisy in a sympathetic light, she is merely sad in terms of being trapped in her relationship with the brutish Tom. Yet, her lack of tragedy is because she does not sacrifice, does not lose in the process. She hedges her bets and stays with the source of wealth in Tom. Gatsby surrenders everything in order to have her. While the pursuit of her might not be true love, as much as simply a desire to have an ideal, Gatsby pursues it with reckless abandon. His desire to appropriate the world in accordance to his own subjectivity, failing to understand his own shortcomings and the pursuit's own shortcomings result in the tragedy that is evident. It is here where the greater tragic figure is Gatsby. His being the embodiment of dreams and of pain are the realities that define his tragic being. Daisy never comes close to representing the death of dreams and the pain of subjectivity that Gatsby does. It is in this where I think that Gatsby has to represent the greater tragic condition between the two.