The qualified electors shall have the power to recall any elective officer whether elected by popular vote or selected to fill a vacancy, and may exercise such power by filing with the City Clerk a petition signed by qualified electors of the City equal in number to at least twenty per centum of the registered voters at the last general municipal election. The petition shall be signed and verified in the manner required for an initiative petition, shall contain a demand for the removal of the elective officer, and shall contain a general statement of the reasons for which the removal is sought.