IL SB1456

Requires all State-administered presidential primary elections in Illinois to use ranked choice voting, allowing voters to rank up to 5 candidates in order of preference (minimum 3 rankings if equipment limitations exist).

Political parties must notify the State Board of Elections at least 150 days before the primary whether they want winner-take-all or proportional delegate allocation; if no preference is specified, tabulation defaults to statewide winner-take-all basis.

Establishes tabulation process where the candidate with the fewest votes is eliminated each round, with those votes transferred to voters' next-ranked active candidate, continuing until a winner is determined or all active candidates meet the delegate threshold.

Requires State Board of Elections to release unofficial preliminary round-by-round results and cast vote records online as soon as feasible after polls close and at regular intervals during counting, clearly labeled as preliminary.

Ballots become inactive if they contain no active candidates, have an overvote (multiple candidates ranked at same level), or have 2 consecutive skipped rankings; undervotes do not count in any round.