Illinois's 16th congressional district

The congressional district covers parts of DeKalb, Ford, Stark, Will and Winnebago counties, and all of Boone, Bureau, Grundy, Iroquois, LaSalle, Lee, Livingston, Ogle and Putnam counties, as of the 2011 redistricting which followed the 2010 census. All or parts of Belvidere, Channahon, DeKalb, Dixon, Loves Park, Machesney Park, Ottawa, Morris, Pontiac, Rockford and Streator are included.[4] The representatives for these districts were elected in the 2012 primary and general elections, and the boundaries became effective on January 5, 2013.

Prominent past representatives from the 16th district have included Everett Dirksen, who went on to become the Republican leader in the United States Senate; John B. Anderson, who became the 3rd highest ranking Republican in the House and went on to run as a major independent candidate in the 1980 Presidential election; and Lynn Martin, who later served as United States Secretary of Labor.

For decades, the 16th district was the most geographically stable district in Illinois. For more than six decades, in comparison to the other districts in the state, it was almost stationary. While its shape fluctuated slightly after each census, in general it included the northwest corner of the state, extending just far enough to the east to grab its largest city, Rockford.[5] By the 1990s, it extended eastward to include part of McHenry County, an outer suburb of Chicago. This geographic stability also contributed to electoral stability. It first became a Rockford-based district for the 1948 election, and from then until 2012 it was represented by just five people, all but one of whom was a Republican. The sole Democrat to have held it in that period, John W. Cox, Jr., only did so for one term.

However, with the new map drawn for 2012, the familiar shape of the 16th was rendered unrecognizable. It was pushed well to the east to include the southwestern exurbs of the Chicago metropolitan area, and stretches from the Wisconsin border to the Indiana border. While it still included most of Rockford's suburbs, half of Rockford itself—essentially the more Democratic portion of the city—was shifted to the 17th district.

• Illinois's congressional districts
• List of United States congressional districts

• Martis, Kenneth C. (1989). The Historical Atlas of Political Parties in the United States Congress. New York: Macmillan Publishing Company.
• Martis, Kenneth C. (1982). The Historical Atlas of United States Congressional Districts. New York: Macmillan Publishing Company.
• Congressional Biographical Directory of the United States 1774–present

• Washington Post page on the 16th District of Illinois
• U.S. Census Bureau - 16th District Fact Sheet