Mississippi Code Title 23. Elections § 23-15-853

(1) If a vacancy occurs in the representation in Congress, the vacancy shall be filled for the unexpired term by a special election, to be ordered by the Governor, within sixty (60) days after the vacancy occurs, and held at a time fixed by his or her order, and which time shall be not less than sixty (60) days after the issuance of the order of the Governor, which shall be directed to the election commissioners of the several counties of the district, who shall, immediately on the receipt of the order, give notice of the election by publishing the same in a newspaper having a general circulation in the county and by posting the notice at the front door of the courthouse. The order shall also be directed to the State Board of Election Commissioners. The election shall be prepared for and conducted, and returns shall be made, in all respects as provided for a special election to fill vacancies.

(2) Candidates for the office in such an election must qualify with the Secretary of State by 5:00 p.m. not less than fifty (50) days before the date of the election. If the fiftieth day to qualify before an election falls on a Sunday or legal holiday, the qualification submitted on the business day immediately following the Sunday or legal holiday shall be accepted. The election commissioners shall have printed on the ballot in such special election the name of any candidate who shall have been requested to be a candidate for the office by a petition filed with the Secretary of State and personally signed by not less than one thousand (1,000) qualified electors of the district. The petition shall be filed by 5:00 p.m. not less than fifty (50) days before the date of the election. If the fiftieth day to file the petition before an election falls on a Sunday or legal holiday, the petition filed on the business day immediately following the Sunday or legal holiday shall be accepted.

There shall be attached to each petition above provided for, upon the time of filing with the Secretary of State, a certificate from the appropriate registrar or registrars showing the number of qualified electors appearing upon each petition which the registrar shall furnish to the petitioner upon request.