CREATE TABLE table_28911 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" TEXT, "Result" TEXT, "Candidates" TEXT)

Who is every incumbent when Kentucky 2 is the district?
SELECT "Incumbent" FROM table_28911 WHERE "District" = 'Kentucky 2'
SELECT "Incumbent" FROM "table_28911" WHERE "District" = 'Kentucky 2'