Behind Illinois' Blue Façade, Growing Partisan Polarization
Illinois' rural-suburban/urban divide is growing
When it comes to presidential elections, Illinois has been consistently blue for decades. The last GOP candidate to claim the state’s electoral college votes was George H.W. Bush, in 1988. In the last three elections—2012, 2016 and 2020—the Democratic candidate won by about 17 percentage points.
But look closer and the bright blue picture gets more complicated. Across Illinois, two shifts in voting for the two major parties have occurred in recent years that mirror national trends, as our county-by-county review of presidential election results since 2012 shows. First, Chicago’s suburban “collar counties” are growing more Democratic. Second, downstate is getting redder.
Anyone with more than a passing familiarity with Illinois politics knows “Chicagoland” and the rest of Illinois can feel like two different worlds. But geographic polarization appears to be growing. In terms of voting habits, the rural vs. suburban-urban divide is widening. Among Illinois’ 20 largest cities all sit in counties that went for Joe Biden this year, except Springfield and Decatur.
“We’re seeing rural areas trending hard Republican, and we’re seeing suburbs get more split,” says Scott Kennedy, a consultant with A/L Media who has worked on Democratic campaigns.
As Illinois goes, so goes the nation, indeed.
Interactive maps displaying the percentage of votes the winning party received in each county in the last three presidential elections can be found here:
GOP’s Downstate Dominance Grows
For a dramatic example of the GOP’s growing strength in deep-south Illinois, take a look at Gallatin County. Bordering Indiana and Kentucky, it’s one of the least-populous counties in Illinois, with fewer than 5,000 people. About 97% of residents are white.
Trump just won the county with about 76% of the vote, growing his support 4 percentage points since 2016. Mitt Romney won the county in 2012 with 58% of the vote.
The darkening shade of red in this county is remarkable given Gallatin was a Democratic stronghold throughout the 20th century. In 1994, it was the only county in Illinois that GOP Governor Jim Edgar lost (although the margin for his opponent, Dawn Clark Netsch, was only 0.1%).
“Deep southern Illinois used to be a fairly Democratic area,” Kennedy says, noting there were once many union mine workers in the region. But in the three most recent presidential elections, nearly every county south of Champaign County has seen the GOP candidate post larger victories.
A few examples: In 2012, Romney won Marion, Franklin and Jefferson counties with between 57% and 60% of the vote. Trump built on those margins in 2016 and again in 2020, when he pulled in 71.7-73.1% of the vote in those three counties.
“In the last 15 years, you’ve seen everything from Effingham to the Kentucky border, which used to be represented by Democrats, is now won by Republicans,” Kennedy says.
This year, Joe Biden carried just two counties in the southern half of the state. St. Clair—which borders Missouri, contains East St. Louis and is about 30% African-American—went Democratic with 53.3% of the vote, 3 points higher than in 2016. Biden won Jackson County this year with a 49.38% plurality of votes. That was a few points higher than in 2016, but below the 56% Barack Obama claimed in 2012.
Northwest and Central Regions Growing Red as Well—With One Exception
Northwest Illinois counties saw their biggest shift occur between 2012 and 2016. These counties stretch from Jo Daviess on the Wisconsin border down to Henderson on the Iowa border, and over to Knox and Fulton just west of Peoria.
Obama won a swath of 11 counties in this region while getting re-elected. In 2016 and 2020, they all went red, except for Rock Island, part of the Quad Cities region. But this likely had much to do with the home state-favorite effect and the exposure of these to pro-Obama ads in eastern Iowa’s media market, Kennedy says.
The more recent trend in the state’s northwest region is in line with the GOP’s growing rural grip. With Obama off the ballot after 2012, 10 counties in the region flipped red in 2016 and remained red this year. With the exception of Rock Island, Trump won a greater share of the vote in every northwest county while up for re-election —from Jo Daviess and Stephenson in the north, down to Henderson, Warren, Knox, Stark and Marshall.
Central Illinois experienced the same trend—except for McLean County, home to Bloomington-Normal and Illinois State University, where the reverse was true. Romney won it outright in 2012, while Trump pulled a plurality of 46.6% votes in 2016. This year? It flipped to Biden, who won 50.5% of votes.
“Historically, it’s been a very red county,” Kennedy says. But anti-Trump forces seem to have energized McLean’s Democratic Party, driving registration and voter turnout. “Someone must have figured out how to energize not only the campus vote, but faculty and the larger university community. From a Democratic point of view, that’s one of the bright spots this year.”
Beyond McLean, Peoria and Champaign (home to University of Illinois at Urbana-Champaign) were the only other blue counties in central Illinois this year.
Chicagoland Counties Keep Breaking Blue
Much has been made this election cycle of the pivotal role suburbs played around the country in pushing Biden to victory. As they grow more diverse by race, ethnicity and class, they are becoming more Democratic.
You can see this trend playing out since 2012 in the five “collar” counties abutting Chicago (Lake, McHenry, DuPage, Kane, Will), as well as nearby DeKalb and Kendall. With DeKalb flipped blue in 2016 and Kendall flipping blue this year, for the first time in recent history, just one of these seven Chicagoland counties went for the GOP presidential candidate: McHenry, which barely went for Trump with 50.2% of the vote.
Here’s the breakdown* of all seven counties stretching back to 2012:
*All figures rounded. A party winning with less than 50% of vote had a plurality.
Kennedy was surprised to see McHenry still red this time around. It could very well flip in 2024, as demographics continue to shift and more households become solidly Democratic.
“The shift in the suburbs is real,” Kennedy says, noting that the shift toward the Democratic Party manifests not just in presidential elections but also in county-level elections and congressional races. “You have a lot more split households—one spouse voting GOP, one spouse voting Dem.”
**Wagner Acerbi Horta contributed
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