In each year of the general election at which electors of President and Vice President of the United States are to be chosen, each congressional nominee shall designate one presidential elector and shall file his or her name, residence and business address with the Secretary of State by October 1 of the presidential election year. Each United States senatorial nominee, determined by the last two United States senatorial elections, shall designate one presidential elector and shall file his or her name, residence and business address with the Secretary of State by October 1 of the presidential election year. In the event there is no United States senatorial nominee or no congressional nominee in any particular district, the state chairperson shall designate one presidential elector for each vacancy and shall file his or her name, residence and business address with the Secretary of State by October 1 of the presidential election year.