CREATE TABLE table_43539 ("Round" FLOAT, "Race Name" CLOB, "Circuit" CLOB, "City/Location" CLOB, "Date" CLOB)

What round was the circuit portland international raceway?
SELECT "Round" FROM table_43539 WHERE "Circuit" = 'portland international raceway'
SELECT "Round" FROM "table_43539" WHERE "Circuit" = 'portland international raceway'