Nobody thinks the Cuban vote will help Clinton. Cubans always have been mostly Republican in FL- although the younger generation isn't strong R like their parents and grandparents.
It's the other Latino groups in FL that are helping Clinton. Mostly the Puerto Rican voters in the metro Orlando area and there are a large number of them. They are mostly Clinton supporters and Democrats.
As Florida's Hispanic vote grows, Puerto Ricans help Democrats
...
The increase in these new Puerto Rican voters suggest a shift away from the more conservative Cuban-American vote that has long defined Florida's Hispanic electorate, said Daniel Smith, a University of Florida professor who studies voting trends.
In 1990, Cubans were nearly half of Florida's Hispanic voting population.
In 2014, they were 31 percent, and Puerto Ricans were 27 percent...
Of the state's 818,540 newly registered voters this year, 185,905 are Hispanics nearly evenly split at 42 percent between Democrats and Non Party Affiliates, with almost 15 percent registered as Republicans,