What is the most popular race in Houston?

Excuse me, but could you please clarify for me which aspect of "race" you're referring to in the context of Houston? Are you inquiring about the most populous ethnic group, the most popular sporting event involving runners, or perhaps something else entirely? If you're asking about the ethnic group with the largest population in Houston, it's a diverse city with many different ethnicities represented, so it may be difficult to pinpoint a single "most popular" race. However, if you're referring to something else, please provide more context so I can give you an accurate answer.