2026 midterms · Illinois
18 of 102 counties have more registrations than the Census counts adult citizens; 15 of them by more than the Census margin of error.
Registrations ÷ Census adult citizens
99.7%
9,067,966 A + I (the Registration Counts page's "active and inactive totals") against 9,094,968 ± 11,081 adult citizens
Counties over 100%
18 of 102
15 beyond the Census margin of error
Swing since 2024
Pending
2026 county results are still to come.
Results: Illinois’s State Board of Elections posts county vote totals after its canvass; until then, each county’s election authority posts its own.
Certification: The State Board of Elections canvasses and proclaims results within 31 days of the election, by December 4. Source
Registration file: A + I (the Registration Counts page's "active and inactive totals"). Registration Counts page, live counts saved by hand November 10, 2026.
Next, December 4: the State Board of Elections’ proclamation. Source
Illinois’s file splits active and inactive registrations. The maps use the total, 99.7% of adult citizens; active registrations alone come to 91.8%.
Each county is colored by its registrations (A + I (the Registration Counts page's "active and inactive totals")) as a share of the Census count of its adult citizens. Gray is 100% or less; the amber steps are over 100%, darker for more.
| County | Registrations ÷ adult citizens | Registrations | Adult citizens | Swing since 2024 | Turnout |
|---|---|---|---|---|---|
| Adams County | 99.8% | 49,801 | 49,877 | — | — |
| Alexander County | 127.1% | 4,853 | 3,819 | — | — |
| Bond County | 81.4% | 11,119 | 13,653 | — | — |
| Boone County | 97.2% | 36,682 | 37,733 | — | — |
| Brown County | 65.2% | 3,393 | 5,203 | — | — |
| Bureau County | 94.7% | 24,286 | 25,652 | — | — |
| Calhoun County | 89.4% | 3,096 | 3,465 | — | — |
| Carroll County | 91.4% | 11,497 | 12,585 | — | — |
| Cass County | 93.5% | 7,914 | 8,464 | — | — |
| Champaign County | 82.0% | 123,668 | 150,737 | — | — |
| Christian County | 83.8% | 22,548 | 26,891 | — | — |
| Clark County | 106.0% | 12,455 | 11,748 | — | — |
| Clay County | 96.1% | 9,538 | 9,925 | — | — |
| Clinton County | 92.2% | 26,343 | 28,565 | — | — |
| Coles County | 82.1% | 30,896 | 37,638 | — | — |
| Cook County | 102.9% | 3,693,421 | 3,590,885 | — | — |
| Crawford County | 89.4% | 13,152 | 14,708 | — | — |
| Cumberland County | 97.4% | 7,797 | 8,009 | — | — |
| DeKalb County | 100.0% | 75,684 | 75,692 | — | — |
| De Witt County | 90.4% | 10,842 | 11,998 | — | — |
| Douglas County | 85.5% | 12,388 | 14,493 | — | — |
| DuPage County | 108.2% | 705,264 | 651,651 | — | — |
| Edgar County | 94.2% | 12,435 | 13,196 | — | — |
| Edwards County | 93.3% | 4,398 | 4,714 | — | — |
| Effingham County | 95.0% | 24,657 | 25,950 | — | — |
| Fayette County | 85.9% | 14,493 | 16,874 | — | — |
| Ford County | 100.0% | 10,094 | 10,093 | — | — |
| Franklin County | 98.4% | 28,393 | 28,842 | — | — |
| Fulton County | 93.9% | 24,736 | 26,338 | — | — |
| Gallatin County | 91.8% | 3,510 | 3,825 | — | — |
| Greene County | 97.8% | 8,905 | 9,102 | — | — |
| Grundy County | 101.5% | 40,279 | 39,697 | — | — |
| Hamilton County | 92.3% | 5,697 | 6,171 | — | — |
| Hancock County | 93.0% | 12,541 | 13,489 | — | — |
| Hardin County | 97.9% | 3,005 | 3,069 | — | — |
| Henderson County | 92.4% | 4,650 | 5,035 | — | — |
| Henry County | 94.0% | 35,558 | 37,817 | — | — |
| Iroquois County | 95.8% | 19,381 | 20,232 | — | — |
| Jackson County | 84.6% | 34,834 | 41,166 | — | — |
| Jasper County | 92.4% | 6,499 | 7,035 | — | — |
| Jefferson County | 88.8% | 24,985 | 28,127 | — | — |
| Jersey County | 96.2% | 16,280 | 16,924 | — | — |
| Jo Daviess County | 99.4% | 17,621 | 17,720 | — | — |
| Johnson County | 81.5% | 8,806 | 10,801 | — | — |
| Kane County | 95.6% | 334,266 | 349,478 | — | — |
| Kankakee County | 92.4% | 73,605 | 79,689 | — | — |
| Kendall County | 113.8% | 106,491 | 93,541 | — | — |
| Knox County | 87.2% | 33,220 | 38,111 | — | — |
| Lake County | 106.4% | 515,679 | 484,882 | — | — |
| LaSalle County | 100.3% | 83,980 | 83,702 | — | — |
| Lawrence County | 76.2% | 9,221 | 12,100 | — | — |
| Lee County | 87.3% | 23,370 | 26,757 | — | — |
| Livingston County | 87.4% | 23,947 | 27,396 | — | — |
| Logan County | 84.8% | 18,812 | 22,171 | — | — |
| McDonough County | 86.5% | 18,689 | 21,612 | — | — |
| McHenry County | 99.0% | 225,360 | 227,708 | — | — |
| McLean County | 98.5% | 126,339 | 128,316 | — | — |
| Macon County | 98.0% | 75,975 | 77,500 | — | — |
| Macoupin County | 91.2% | 31,975 | 35,062 | — | — |
| Madison County | 93.3% | 191,856 | 205,631 | — | — |
| Marion County | 90.6% | 25,398 | 28,046 | — | — |
| Marshall County | 94.2% | 8,659 | 9,195 | — | — |
| Mason County | 94.7% | 9,545 | 10,076 | — | — |
| Massac County | 106.6% | 11,497 | 10,787 | — | — |
| Menard County | 96.5% | 9,084 | 9,411 | — | — |
| Mercer County | 103.7% | 12,670 | 12,217 | — | — |
| Monroe County | 112.1% | 30,544 | 27,239 | — | — |
| Montgomery County | 79.4% | 17,664 | 22,253 | — | — |
| Morgan County | 82.5% | 21,980 | 26,641 | — | — |
| Moultrie County | 85.1% | 9,144 | 10,742 | — | — |
| Ogle County | 95.4% | 37,116 | 38,925 | — | — |
| Peoria County | 99.7% | 130,746 | 131,077 | — | — |
| Perry County | 77.3% | 12,773 | 16,531 | — | — |
| Piatt County | 100.5% | 13,060 | 12,992 | — | — |
| Pike County | 93.3% | 10,290 | 11,025 | — | — |
| Pope County | 90.0% | 2,866 | 3,183 | — | — |
| Pulaski County | 108.9% | 4,330 | 3,975 | — | — |
| Putnam County | 91.5% | 4,106 | 4,487 | — | — |
| Randolph County | 84.4% | 19,848 | 23,513 | — | — |
| Richland County | 93.9% | 11,167 | 11,898 | — | — |
| Rock Island County | 87.0% | 91,266 | 104,875 | — | — |
| St. Clair County | 99.0% | 189,979 | 191,810 | — | — |
| Saline County | 88.4% | 16,172 | 18,302 | — | — |
| Sangamon County | 103.6% | 154,585 | 149,253 | — | — |
| Schuyler County | 88.5% | 4,975 | 5,624 | — | — |
| Scott County | 91.4% | 3,551 | 3,884 | — | — |
| Shelby County | 95.1% | 15,445 | 16,235 | — | — |
| Stark County | 83.6% | 3,428 | 4,100 | — | — |
| Stephenson County | 90.1% | 30,583 | 33,948 | — | — |
| Tazewell County | 84.9% | 85,589 | 100,864 | — | — |
| Union County | 98.8% | 13,040 | 13,199 | — | — |
| Vermilion County | 88.2% | 48,584 | 55,108 | — | — |
| Wabash County | 90.1% | 7,830 | 8,690 | — | — |
| Warren County | 101.5% | 12,290 | 12,104 | — | — |
| Washington County | 96.3% | 10,351 | 10,748 | — | — |
| Wayne County | 91.9% | 11,145 | 12,122 | — | — |
| White County | 96.7% | 10,272 | 10,620 | — | — |
| Whiteside County | 93.0% | 39,203 | 42,143 | — | — |
| Will County | 95.9% | 477,080 | 497,634 | — | — |
| Williamson County | 104.1% | 54,168 | 52,032 | — | — |
| Winnebago County | 99.8% | 204,867 | 205,347 | — | — |
| Woodford County | 103.6% | 29,897 | 28,849 | — | — |
Results pending: Illinois’s State Board of Elections posts county vote totals after its canvass; until then, each county’s election authority posts its own. Next, December 4: the State Board of Elections’ proclamation.
Alphabetical. Each entry gives the county’s registrations against the Census count of adult citizens, its ballots, and its swing since 2024, with the file each figure comes from.
Every figure on this page is computed from the files listed below when the page is built. The registration count is the state’s own, under the state’s own label. The adult-citizen count is the Census Bureau’s citizen voting-age population from its special tabulation of the American Community Survey for 2020 to 2024, which carries a margin of error for every area; a county is “over within the margin” when its registrations pass the estimate by less than that margin.
The ratio to all adults uses the Census Bureau’s Vintage 2025 estimates of every resident of voting age, citizen or not, as of July 2025. Turnout is ballots cast divided by registrations, using the state’s own label for its ballots count; where a state publishes no ballots count, the votes in the race shown stand in, and the entry says so.
The swing is the Democratic share of the two-party vote in the 2026 race shown, minus the Democratic share in the 2024 presidential race, in percentage points. The race is the US Senate where the Democrat and the Republican each drew more votes than all other candidates together; otherwise the governor’s race; otherwise the US House, summed over each county’s contested districts. Votes are counted on the Democratic and Republican lines only; votes for the same candidates on other party lines are counted with the other candidates. Under ranked choice, first choices are used. The 2024 baseline is the MIT Election Data and Science Lab’s county file.
These pages describe the numbers. They are kept apart from the tests we registered in advance for our own analysis of the 2026 returns. Unofficial results move during the canvass; each figure carries the time of the file it came from, and the pages are rebuilt as states certify and post new registration files.
| What | File | As of |
|---|---|---|
| Registration: A + I (the Registration Counts page's "active and inactive totals") | www.elections.il.gov | Registration Counts page, live counts saved by hand November 10, 2026 |
| Census adult citizens (CVAP), ACS 2020–2024 special tabulation | www2.census.gov | published 2026 |
| Census adult residents, Vintage 2025 estimates | www2.census.gov | July 1, 2025 |
| 2024 president by county, MIT Election Data and Science Lab | doi.org | certified 2024 returns |