CREATE TABLE table_28884 ("District" CLOB, "Incumbent" CLOB, "Party" CLOB, "First elected" CLOB, "Result" CLOB, "Candidates" CLOB)

Who were the candidates for election that had a result of a retired jacksonian gain?
SELECT "Candidates" FROM table_28884 WHERE "Result" = 'Retired Jacksonian gain'
SELECT "Candidates" FROM "table_28884" WHERE "Result" = 'Retired Jacksonian gain'