This article is about the suburban counties outside Chicago. For the four suburban Philadelphia counties (Delaware, Montgomery, Bucks, and Chester) also known as "the collar counties"[1][2][3], see Delaware Valley.
This article needs attention from an expert in Illinois or Politics of the United States. The specific problem is: Needs expansion and updates, especially by people who closely follow Illinois politics.WikiProject Illinois or WikiProject Politics of the United States may be able to help recruit an expert.(September 2018)
Clockwise from top left: Rialto Square Theater (Joliet), Downtown Crystal Lake, Moser Tower (Naperville), Old DuPage County Courthouse (Wheaton), Great Lakes Naval Training Station (North Chicago) and Downtown Aurora.
After Cook County, the collar counties are also the next five most populous counties in Illinois. According to the Encyclopedia of Chicago, there is no specifically known origin of the phrase, but it has been commonly used among policy makers, urban planners, and in the media.[4]
In 1950, the Census Bureau defined the Chicago metropolitan statistical area as comprising Cook County, four of the five collar counties (excluding McHenry), and Lake County in Indiana. In 2010, reflecting urban growth, the Bureau redefined the area as comprising several additional counties in Illinois, Indiana, and Wisconsin.[5]
As of 2019, there are 3,150,376 people residing in the collar counties, nearly 25% of the population of Illinois. Cook County and the collar counties combined are home to approximately 65% of Illinois's population.
Use in political discussions
While it is not its exclusive use, the term is often employed in political discussions.[6][7] Like many other suburban areas in the United States, the collar counties have somewhat different political leanings from the core city. Chicago has long been a Democratic stronghold, while the collar counties historically tilted Republican. In recent elections, however, the collar counties have voted for Democrats, but with lower margins than Cook County.[8]
Because Cook County tends to vote for Democrats by large margins, and downstate Illinois tends to vote for Republicans by large margins, the collar counties are routinely cited as being the key to any statewide election.[9][10][11] However, that conventional wisdom was challenged in the 2010 gubernatorial election, as Democrat Pat Quinn won election while winning only Cook County and three counties in Southern Illinois.[12] All five collar counties went Republican, so the key to that gubernatorial election was winning Cook County by a wide enough margin to overwhelm the rest of the state.
^Mariner, Richard D. (2005), "Collar Counties", Encyclopedia of Chicago, Chicago: Chicago History Museum and the Newberry Library, retrieved March 11, 2021