Like many state and national political races, the path to being elected governor of Illinois runs through suburbia:

In 2014, Rauner defeated former Democratic Gov. Pat Quinn with a big assist from DuPage, Kane, Lake, McHenry and Will counties. The Chicago region contributed 62 percent of statewide votes for governor in 2014. Without Chicago, the suburbs generated 44 percent of ballots cast in Illinois…

Reason No. 1 “is the raw number of independent/swing voters in the collar counties,” Morris said…

Another lure for Pritzker and Rauner is that collar county turnout is typically higher compared to elsewhere during nonpresidential election years, analysts say…

A final reason for the suburban surge is bragging rights. With the future of the presidency looming large, both candidates want their coattails to decide the fate of congressional seats in play like the 6th District.

With over 50% of Americans living in suburbs and consistent patterns of urban residents voting for Democrats and rural voters going for Republicans, this is the truly purple part of America. And, we can probably be even more specific about which suburban voters by geography are up for grabs: those living in inner-ring suburbs and closer to the big city lean Democratic and those farther out and on the exurban fringe lean Republican. These patterns are replicated in Illinois: Chicago will deliver big votes for Pritzker, downstate/more rural Illinois will deliver votes for Rauner, and the winner will be decided by suburbanites who often can be swayed.

It would be fascinating to see the suburban microtargeting data of both Illinois candidates. Does Pritzker think there are enough working-class suburbanites? Does Rauner think generally favorable economic conditions in the conditions lifted the boats of enough suburbanites to vote Republican? Who targets which suburban racial and ethnic groups? While the article suggests both candidates are making numerous suburban campaign stops, it might be worth keeping track of which suburbs and which groups receive attention.