Joseph Campbell's Hero's Journey regards the supernatural aide as the helper, the mentor, the one person that gives the hero instructions that he or she could not receive any other way or from any other person. It is why the helper is considered supernatural, because he or she seems to come from out of nowhere.
In the novel, Hard Luck, Jake Adams struggles as the underdog of Eddie McIntyre. Eddie's searing put downs, which appear as joking around, means Jake not only questions Eddie's friendship, he compares himself to Eddie constantly. This exacts jealousy, which only frustrates Jake even more.
As a result, when Jake meets the Apache on the job, he is taught he doesn't have to put up with anything that penetrates his psyche the way that Eddie does. In other words, the Apache understands Jake's frustration and shows him ways to cope.
The summer of 1931 without unions in place to establish regulations to protect the workers from extreme working conditions, and carrying fears of unemployment just beneath the surface, these men were examples of their own kind of tough. They had to look out for, whether they knew it or not, someone or something to help them in a way that wouldn't change the hardship but change their ability to deal with it.
As the desert was unforgiving, the work unforgiving, the men forgave the conditions surrounding them and forged on, each with a supernatural aide, a helper, somebody in their lives that provided the supernatural help needed to endure.