Of Mice and Men is an allegory. What symbols would you use for Crooks and Candy?

Candy is the easier of the two to assign allegorical meaning to.
Many people would associate "candy" with something that many people need, want, and/or desire. 
Here, Candy is the exact opposite.  Since the loss of his hand, Candy has become more of a
fixture than an actual necessary "piece" of the farm workers.  Others feel sorry for him and
tolerate him simply because of his handicap. Therefore, he is not as needed, wanted, or desired
as a completely healthy worker.

Crooks' allegorical understanding
can be deceiving.  While literally Crooks is bent physically, he may be seen to be bent mentally
and emotionally as well.  While some may understand "crooks" to be a form of crooked (meaning not
morally correct), this is not so for Crooks in Of Mice and Men. Crooks feels
isolated from the other workers because of his race.  This isolation affects him both mentally
and emotionally; therefore, he has become emotionally and mentally
crooked.