CREATE TABLE table_781 ("District" CLOB, "Incumbent" CLOB, "Party" CLOB, "First elected" FLOAT, "Result" CLOB, "Candidates" CLOB)

how many incumbent with first elected being 1924
SELECT COUNT("Incumbent") FROM table_781 WHERE "First elected" = '1924'
SELECT COUNT("Incumbent") FROM "table_781" WHERE "First elected" = '1924'