CREATE TABLE table_18139 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Results" TEXT, "Candidates" TEXT)

Who's the incumbent of Florida 12 district?
SELECT "Incumbent" FROM table_18139 WHERE "District" = 'Florida 12'
SELECT "Incumbent" FROM "table_18139" WHERE "District" = 'Florida 12'