CREATE TABLE table_28939 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" TEXT, "Result" TEXT, "Candidates" TEXT)

Name the number of first elected for john smith
SELECT COUNT("First elected") FROM table_28939 WHERE "Incumbent" = 'John Smith'
SELECT COUNT("First elected") FROM "table_28939" WHERE "Incumbent" = 'John Smith'