Where Cockroach Legs and Snow White Have Something in Common

When Jon Cruz was 8, he flaunted a “Ross Perot for President” pin nearly every day at school. It was 1992, and Mr. Perot was running as an independent candidate.

“I was trying to talk to adults about Nafta,” said Mr. Cruz, now 31 and a government teacher at the Bronx High School of Science.

His passion for presidential campaign memorabilia exploded from t…