Table schema:
CREATE TABLE table_name_19 (runner_s__up VARCHAR, margin_of_victory VARCHAR, winning_score VARCHAR)

Question: Who is runner-up where the winning score is –6 (65-70-70-69=274) and the margin of victory is 3 strokes?
SQL: SELECT runner_s__up FROM table_name_19 WHERE margin_of_victory = "3 strokes" AND winning_score = –6(65 - 70 - 70 - 69 = 274)