CREATE TABLE table_18724 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Result" TEXT, "Candidates" TEXT)

Who were the candidates when Henry Garland Dupr was incumbent?
SELECT "Candidates" FROM table_18724 WHERE "Incumbent" = 'Henry Garland Dupré'
SELECT "Candidates" FROM "table_18724" WHERE "Incumbent" = 'Henry Garland Dupré'