(2) The Secretary of State by rule may adopt a schedule for filing nominating petitions or declarations of candidacy under this section. The schedule may specify the period within which nominating petitions or declarations of candidacy must be filed after a vacancy occurs. [Formerly 252.060; 1981 c.173 §25; 1983 c.7 §2; 1983 c.567 §8; 1985 c.808 §17; 1995 c.607 §18; 1999 c.318 §4]