Table schema:
CREATE TABLE table_19312274_2 (total VARCHAR, last_current_driver_s_ VARCHAR)

Question: how many total where last/current driver(s) is narain karthikeyan ( 2010 )
SQL: SELECT COUNT(total) FROM table_19312274_2 WHERE last_current_driver_s_ = "Narain Karthikeyan ( 2010 )"