CREATE TABLE table_72663 ("Year" FLOAT, "Dates" CLOB, "Champion" CLOB, "Country" CLOB, "Score" CLOB, "To par" CLOB, "Margin of victory" CLOB, "Purse  (  US$  ) " FLOAT, "Winners share" FLOAT)

What countries have a margin of victory at 6 strokes?
SELECT "Country" FROM table_72663 WHERE "Margin of victory" = '6 strokes'
SELECT "Country" FROM "table_72663" WHERE "Margin of victory" = '6 strokes'