CREATE TABLE table_52966 ("Year" FLOAT, "Stage" FLOAT, "Category" TEXT, "Start" TEXT, "Finish" TEXT, "Leader at the summit" TEXT)

Who was the leader at the summit for the race in 2005?
SELECT "Leader at the summit" FROM table_52966 WHERE "Year" = '2005'
SELECT "Leader at the summit" FROM "table_52966" WHERE "Year" = '2005'