CREATE TABLE table_18451 ("District" CLOB, "Incumbent" CLOB, "Party" CLOB, "First elected" FLOAT, "Result" CLOB, "Candidates" CLOB)

In what year was John Bell Williams first elected?
SELECT "First elected" FROM table_18451 WHERE "Incumbent" = 'John Bell Williams'
SELECT "First elected" FROM "table_18451" WHERE "Incumbent" = 'John Bell Williams'