Illinois Redistricting: A Growing Swing Vote?

In Illinois, the places that are growing the fastest are also the ones that are up for grabs between Democrats and Republicans. Does this growth in Chicago's suburbs and exurbs mean that the state's politics will be more competitive after redistricting?
by | May 21, 2010

Between 2000 and 2009, Illinois' population increased by just a hair under 500,000 according to Census Bureau estimates. Illinois has 102 counties. Yet just six counties can account for the entire of population growth. Together, Will County, Kane County, Lake County, McHenry County, Kendall County and DuPage County have gained about 500,000 people.

These counties and a few other ones in Illinois that are gaining substantial population are key to understanding how this round of redistricting might change Illinois politics (previous states covered in this series: California, Texas, New York and Florida). Here are the counties that have added at least 10,000 people since 2000.

Illinois Growth Counties

These counties have a lot in common both geographically and politically. They include all of the collar counties -- the five counties that are adjacent to Chicago's Cook County. They also include some of the collar of the collar: counties in the broader Chicagoland area (assuming you have an expansive definition of Chicagoland) and along the Wisconsin border.  The fasting-growing county in the country this decade isn't in Texas or Arizona. It's Illinois' Kendall County, where the county seat of Yorkville is an hour's drive from downtown Chicago -- if the traffic is good. The only two on the list that break from the mold are Champaign County (where the University of Illinois is located) and McLean County (home to Illinois State).

As you can see, President Obama didn't do as well in any of these counties as he did statewide. But, there's a funny thing about Illinois' 2008 election results. Obama did worse than his statewide average in 101 of the state's 102 counties. That's possible because Cook County contains more than 40% of Illinois' population and is overwhelmingly Democratic. Your 6th grade math teacher was right when she said that there's a difference between the mode, median and mean.

As you also can see, Obama won every one of these counties (Blagojevich also won plurality victories in a few of them -- the Green Party candidate in that race took 10% of the vote). That might not sound notable (of course Obama was winning in Illinois!), but actually he lost several dozen downstate counties.

If you compare the map of Obama's 2008 victory in Illinois and Bill Clinton's 1992 victory, the difference is striking. Obama won a bigger victory (25 points to 14 points), but Clinton won more counties. The places in Illinois that Clinton lost were disproportionately in the North, while Obama's defeats mainly were in the South.

To me, the big question in Illinois is whether Obama's victories in Chicagoland merely reflect his Chicago roots or reflect a gradual shift toward the Democrats in the area. After all, this is the only part of the state that really is growing. Most counties in Illinois have lost population over the last decade. Cook County's population dropped by about 90,000 (or 1.67%). Many of the Republican downstate counties dropped too. One way to get a sense of whether Chicagoland's fast-growing counties really are changing politically is to look a little further back in time:

Illinois County History

If you compare Kerry's numbers to Gore's, there isn't much of a trend. Kerry generally did about as well as Gore, just as he did as well statewide.

With Blagojevich, there is more of a shift. Though his statewide percentage of the vote dropped from 2002 to 2006, he actually did better in most of these counties the second time around. The one big exception is that the good people of Winnebago County soured noticeably on Blagojevich from 2002 to 2006, largely because Green Party candidate Rich Whitney won a remarkable 24% of their vote. Arguably, Winnebago County doesn't fit with the other places on the list -- it's closer to Madison, Wisconsin than Chicago (I don't include the two college town counties on this list, since I'd guess their growth is driven by different factors than the jurisdictions closer to Chicago).

One place where there is a notable trend is DuPage County. Kerry did better than Gore, Blagojevich did better in 2006 than he did in 2002 and Obama did way better than any of them in 2008. DuPage is important because it is traditionally very Republican and because it is the second most populous county in Illinois, but it's also growing far more slowly than the other places on the list.

Overall, I'd say that whether or not these places really are turning blue remains in doubt. What's clear is that they're the part of the state that is most seriously contested between the two parties. Cook County will remain Democratic for the foreseeable future. Southern Illinois, with some notable exceptions, tilts toward the Republicans. It's the counties listed above where you can expect vibrant competition between the parties.

Redistricting will shift more seats (both legislative and congressional) to these places. What that might mean is that more moderate lawmakers are elected in Illinois. Lawmakers that represent politically competitive seats, you'd expect, are more likely to tack to the center.

Then again, just because a jurisdiction as a whole is politically competitive, that doesn't necessarily mean that the legislative and congressional districts that are sliced and diced from it will be politically competitive too. Lawmakers in Illinois may find a way to secure their  job security, even if it means they have to draw some ugly, ugly districts.

Josh Goodman
Josh Goodman  |  Former Staff Writer

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