The juxtaposition of characters, within Shirley Jackson's "The Lottery," is subjective. What this means is that it is up to the individual reader to define characters as juxtaposed (contrasted or set side-by-side, so as to compare or contrast). Subjective refers to the idea that each reader defines a character based upon their own ideas and justifications.
That said, a few examples of characters which can be identified as juxtaposed are as follows.
Tessie and Mrs. Delacroix
Tessie is late to the lottery. Mrs. Delacroix, on the other hand, is on time. While it may seem in-coincidental at the time, Tessie is the one who "wins" the lottery. One could consider her lateness as foreshadowing.
Tessie and Bill
Bill openly accepts the fate of his family and wife. Unlike Bill, Tessie argues her family's "win" and her "win." Bill readily accepts the lottery as concrete; whereas, Tessie argues that it was not fair.
Tessie and Little Dave
Here, Tessie represents the matriarch of the family, the older woman. Little Dave, on the other hand, represents the youth and future of the Hutchinson family.
Mr. Adams and Tessie
When examining the text from a religious perspective, Mr. Adams represents the biblical Adam and Tessie represents Eve. This juxtaposition speaks to the earliest sin. The villagers, regardless of the tradition, commit murder (which is a sin).