What tournament had a winning score of −27 (64-64-61=189)?
CREATE TABLE "champions_tour_wins_8" (
  "date" text,
  "tournament" text,
  "winning_score" text,
  "margin_of_victory" text,
  "runner_s_up" text
);
SELECT "tournament" FROM "champions_tour_wins_8" WHERE "winning_score"='−27 (64-64-61=189)';