This is my opinion about why Damon should win Elena:
Damon is a much more complicating character than Stefan. He is strong, intelligent, always wears a mask to hide his true feelings and in the beginning he is being presented to us as the bad guy who is proved not to be so bad after all. In reality, if we look a bit deeper, we will find out that Damon hides much more behind that mask than we know.
One thing is certain: the main feelings are pain and rejection. While still human, Damon was constantly overshadowed by his little brother, Stefan. He loved his mother very much, yet she had to die...