10 ILCS 5/7-11
Any candidate for President of the United States may have his name printed upon the primary ballot of his political party by filing in the office of the State Board of Elections not more than 141 and not less than 134 days prior to the date of the general primary, in any year in which a Presidential election is to be held, a petition signed by not less than 3000 or more than 5000 primary electors, members of and affiliated with the party of which he is a candidate, and no candidate for President of the United States, who fails to comply with the provisions of this Article shall have his name printed upon any primary ballot; provided , however, that if the rules or policies of a national political party conflict with such requirements for filing petitions for President of the United States in a presidential preference primary, the Chair of the State central committee of such national political party shall notify the State Board of Elections in writing, citing by reference the rules or policies of the national political party in conflict, and in such case the Board shall direct such petitions to be filed in accordance with the delegate selection plan adopted by the state central committee of such national political party. Provided, further, unless rules or policies of a national political party otherwise provide, the vote for President of the United States, as herein provided for, shall be for the sole purpose of securing an expression of the sentiment and will of the party voters with respect to candidates for nomination for said office, and the vote of the state at large shall be taken and considered as advisory to the delegates and alternates at large to the national conventions of respective political parties; and the vote of the respective congressional districts shall be taken and considered as advisory to the delegates and alternates of said congressional districts to the national conventions of the respective political parties.
10 ILCS 5/7-11