10 ILCS 5/22-7
The State Board of Elections, shall proceed within 31 days after the election, and sooner if all the returns are received, to canvass the votes given for United States Senators and Representatives to Congress, State executive officers, judges of the Supreme Court, judges of the Appellate Court, judges of the Circuit Court, Senators, Representatives to the General Assembly, State's Attorneys and Regional Superintendents of Schools elected from 2 or more counties, respectively, and the persons having the highest number of votes for the respective offices shall be declared duly elected, but if it appears that more than the number of persons to be elected have the highest and an equal number of votes for the same office, the electoral board shall decide by lot which of such persons shall be elected; and to each person duly elected, the Governor shall give a certificate of election or commission, as the case may require, and shall cause proclamation to be made of the result of the canvass, and they shall at the same time and in the same manner, canvass the vote cast upon amendments to the Constitution, and upon other propositions submitted to the electors of the entire State; and the Governor shall cause to be made such proclamation of the result of the canvass as the statutes elsewhere provide. The State Board of Elections shall transmit to the State Comptroller a list of the persons elected to the various offices. The State Board of Elections shall also transmit to the Supreme Court the names of persons elected to judgeships in adversary elections and the names of judges who fail to win retention in office.
No person who is shown by the canvassing board's proclamation to have been elected at the consolidated election or general election as a write-in candidate shall take office unless that person has first filed with the certifying office or board a statement of candidacy pursuant to Section 7-10 or Section 10-5, a statement pursuant to Section 7-10.1, and a receipt for filing a statement of economic interests in relation to the unit of government to which he or she has been elected. For officers elected at the consolidated election, the certifying officer shall notify the election authority of the receipt of those documents, and the county clerk shall issue the certification of election under the provisions of Section 22-18.
10 ILCS 5/22-7