CREATE TABLE table_72419 ("District" TEXT, "Incumbent" TEXT, "Party" TEXT, "First elected" FLOAT, "Result" TEXT, "Candidates" TEXT)

How many in total were elected first in lost renomination?
SELECT COUNT("First elected") FROM table_72419 WHERE "Result" = 'Lost renomination'
SELECT COUNT("First elected") FROM "table_72419" WHERE "Result" = 'Lost renomination'