CREATE TABLE table_18534 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Result" TEXT, "Candidates" TEXT)

What is the party where the incumbent is overton brooks?
SELECT "Party" FROM table_18534 WHERE "Incumbent" = 'Overton Brooks'
SELECT "Party" FROM "table_18534" WHERE "Incumbent" = 'Overton Brooks'