The secretary of state may have one assistant secretary of state, one deputy secretary of state, and one chief of staff each of whom shall have signing authority and be appointed by the secretary in writing, and continue serving at the pleasure of the secretary. The assistant secretary of state, deputy secretary of state, and chief of staff shall have the power to perform any act or duty relating to the secretary of state's office, that the secretary of state has, and the secretary of state shall be responsible for the acts of said assistant, deputy, and chief of staff.