Mayor-elect Brandon Johnson campaigns on the West Side March 26. | Brandon for Chicago campaign

Once Cook County Commissioner Brandon Johnson (1st) is sworn in as Chicago mayor on May 15, Cook County Democratic Party officials will get to work choosing his successor on the Cook County board. 

Under the Cook County Code of Ordinances, vacancies on the county board are filled by the members of the election committee of the political party of the person who last held that seat. The election committees are made up of committeepersons who represent Chicago wards and suburban townships within the district. The committeepersons come together as an election committee, and they can choose any registered voter who lives within the district. 

The replacement is chosen by a majority vote, but each committeeperson’s vote is an equivalent of the percentage of people who voted for the previous commissioner in the last election – which means that the more votes were cast in their ward or township, the more the vote is worth. The replacement will serve out the remainder of Johnson’s term, which ends in 2026. 

Based on the Nov. 8, 2022 election results, the two suburban committeepersons hold a slim majority over the city committeepersons. Ald. Chris Taliaferro (29th), who also serves as the ward committeeperson, said there are currently no firm plans for how he and other officials will approach the process, but the process will start once either Johnson is sworn in as mayor, or, if he chooses to resign from the county board beforehand, whenever he resigns. The county code doesn’t set any time limits on how soon the vacancies are filled, but in past vacancies throughout Cook County, committeepersons tended to move quickly.

Johnson was first elected to the county board in 2018, and his district was remapped in 2022. Under the current map, the city portion includes all of Austin, most of West Garfield Park and portions of East Garfield Park, Humboldt Park and small sections of a few Northwest Side neighborhoods. The suburban portion includes all of Oak Park, Forest Park, Maywood, Bellwood, all but a small section of Broadview, about half of Westchester and small sections of Hillside and North Riverside. 

In Chicago, the 1st District include significant portions of 27th, 28th, 29th and 37th wards, and relatively small portions of 1st, 24th, 26th, 32nd and 36th wards. In the suburbs, it includes the entirety of Oak Park Township and most of Proviso Township.

Illinois Senate President Don Harmon (39th) serves as the Oak Park committeeperson, while Cook County Clerk Karen Yarbrough serves as the Proviso Township committeeperson.

In Chicago, aldermen tend to serve as their wards’ Democratic committeepersons, and the exceptions to this rule tend to have local political connections. Michael Scott, who resigned as 24th Ward alderman in June 2022, remains 24th ward committeeperson. 

Based on the amount of people who voted for Johnson in 2022, Yarbrough has a 23.44% vote share and Harmon has 28.83%. The overall suburban share is 52.27%. The nine city committeepersons collectively have a 47.73% vote share, with Taliaferro holding the highest share, 13.31% of the vote, and Ald. Emma Mitts (37th) holding the second highest share.