this is a list of united states secretaries of state by time in office. this is based on the difference between dates; if counted by number of calendar days all the figures would be one greater. cordell hull is the only person to have served as secretary of state for more than eight years. daniel webster and james g. blaine are the only secretaries of state to have ever served non-consecutive terms. warren christopher served very briefly as acting secretary of state non-consecutively with his later tenure as full-fledged secretary of state. elihu b. washburne served as secretary of state for less than two weeks before becoming ambassador to france.