Bolivia is commonly known as Santa Cruz, please accept that as a type-in. Also, according to the most recent available census data, about 48% of people in the Miami metro area (in the city proper, it's 47%) spoke Spanish at home. Very close, but not quite a majority.
I'm seeing 66% or 59% depending on the source for Miami-Dade County for native speakers, and that doesn't even count people that speak it as a second language. As for Santa Cruz, I will add it as a type-in.