There shall be no primary election for selection of candidates for any elective office of this Village.
   Nominations for each elective Village office shall be made by petition only, on the standard forms provided by the Board of Elections for the nomination of nonpartisan candidates, filed with such Board at least ninety (90) days before the day of election.
   Each petition for the nomination of a candidate for office filled by election at large shall be signed by not less than twenty-five (25) qualified electors from such district.
   Each candidate shall file a separate petition; group petitions shall not be used.
   Nothing in this section shall be construed to prohibit the holding of a caucus by interested electors for the purpose of selecting nominees for elective offices.