In what ways are the characters of "The Lottery" differentiated from one another? Does Jackson make it obvious why Tessie Hutchinson is singled out?

Jackson first groups the characters by gender and age.  The beginning of the story deals with the school-age children, and then the author divides them by gender.  The boys are playing in the dirt and "stuffing" their pockets full of stones, implying that they have natural animalistic tendencies for violence--they seem excited about the morbid reality of the lottery.

Next, the girls are portrayed as standing quietly, almost looking disdainfully at the boys' activities.  The adults follow suit as far as segregating themselves by gender, but all come in their work clothes, symbolizing that the lottery is just another aspect of their duties.

Through characterization, Jackson foreshadows that Tessie Hutchinson will be the "winner" of the lottery.  Very few of the townspeople receive specific characterization by the author, but Tessie does.  She shows up late to the drawing, jokes lightly about almost forgetting the event, and makes her way to her family. As she approaches, people tell her husband, "Here comes your Missus, Hutchinson." This implies that Bill Hutchinson really does not have much control over his wife and that she does what she wants to do, when she wants to do it.  In a town that follows tradition for tradition's sake, this is not an acceptable way of thinking; thus, her "winning" the lottery is in keeping with Jackson's view of social behavior.