Chicago used to have mayoral party primaries, followed by a general election between a Democrat and a Republican. But since 1999, Chicago’s mayoral elections have been nonpartisan: If no one gets a majority of the vote, then there is a runoff between the top two candidates.

The push for nonpartisan elections began after the 1983 election of Harold Washington. In the primary, Washington beat opponents Richard M. Daley and incumbent Mayor Jane Byrne. Voting was largely along racial lines and some politicians then advocated for nonpartisan elections, believing that would reduce the possibility of the white vote being split again in the future.

Springfield lawmakers made the change for Chicago’s mayoral elections in 1995 and the first nonpartisan election was held in 1999.

How might it impact the mayoral election this year? We speak withLarry Bennett, political science professor emeritus at DePaul University.

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