From Debrett's "Presidents of the United States of America"

George HAYES of Windsor, CT (circa 1655-1725)
+Abigail DIBBLE (1667-1725)
Daniel HAYES of Simsbury, CT (1686-1756)
+Sarah LEE (1692-1735) (2nd wife)
Captain Ezekiel HAYES of Branford and New Haven, CT (1724-1807)
+Rebecca RUSSELL (1723-1773)
Ensign Rutherford HAYES of Brattleboro, VT (1756-1636)
+Chloe SMITH (1762-1847)
Rutherford HAYES of Delaware, Ohio (1787-1822)
+Sophia BIRCHARD (1792-1866)
     President Rutherford Birchard HAYES (1822-1893)

That makes George HAYES & Abigail DIBBLE the great-great-great-grandparents of the President.