Here's why:
* Squeaky's (Raymond's sister) desire to win: Squeaky feels compelled to win the May Day race every year, mainly because everyone expects it of her, and she's tired of being labeled as just "Raymond's sister."
* The pressure to conform: The story subtly highlights the societal pressures on girls to be "ladylike" and not engage in athletic pursuits. This pressure is evident in the way Squeaky feels judged for her competitive spirit.
* The judgment of others: Squeaky faces criticism and doubt from others, who underestimate her abilities and dismiss her as just a small girl.
While the story doesn't feature a traditional antagonist, the societal forces that create the pressure on Squeaky and make her fight for recognition are the true antagonists.