CREATE TABLE table_18417 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Result" TEXT, "Candidates" TEXT)

Who ran in the race for the seat of incumbent Carl W. Rich?
SELECT "Candidates" FROM table_18417 WHERE "Incumbent" = 'Carl W. Rich'
SELECT "Candidates" FROM "table_18417" WHERE "Incumbent" = 'Carl W. Rich'