CREATE TABLE table_18691 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Result" TEXT, "Candidates" TEXT)

How many of the first elected were listed when Hatton W. Sumners was incumbent and re-elected?
SELECT COUNT("First elected") FROM table_18691 WHERE "Result" = 'Re-elected' AND "Incumbent" = 'Hatton W. Sumners'
SELECT COUNT("First elected") FROM "table_18691" WHERE "Incumbent" = 'Hatton W. Sumners' AND "Result" = 'Re-elected'