| Illinois fowl? | 14 |
| Illinois governor before Blagojevich | 36 |
| Illinois governor Blagojevich | 29 |
| Illinois home of Black Hawk College | 35 |
| Illinois home of Caterpillar | 28 |
| Illinois home of Rotary International | 37 |
| Illinois home of the John Deere Pavilion | 40 |
| Illinois home to Caterpillar, Inc. | 34 |
| Illinois Indian | 15 |
| Illinois junior senator | 23 |
| Illinois name | 13 |
| Illinois neighbor | 17 |
| Illinois neighbor: Abbr. | 24 |
| Illinois NFL team | 17 |
| Illinois or Colorado city | 25 |
| Illinois or Indiana city | 24 |
| Illinois or Oriental, briefly, in Monopoly | 42 |
| Illinois politician Henry and family | 36 |
| Illinois pop-punkers | 20 |
| Illinois refresher | 18 |
| Illinois representative since 1995 | 34 |
| Illinois river | 14 |
| Illinois River city | 19 |
| Illinois River port | 19 |
| Illinois rockers Sleeping ___ | 29 |
| Illinois senator | 16 |
| Illinois senator Barack | 23 |
| Illinois senator Barack __ | 26 |
| Illinois senator Obama | 22 |
| Illinois senator who became president | 37 |
| Illinois senator-turned-president | 33 |
| Illinois site of a Civil War prison | 35 |
| Illinois state bird? | 20 |
| Illinois state flower | 21 |
| Illinois State University site | 30 |
| Illinois test-marketing town | 28 |
| Illinois time: Abbr. | 20 |
| Illinois town | 13 |
| Illinois town near Champaign | 28 |
| Illinois town near the Mississippi River | 40 |
| Illinois town, site of the first Lincoln-Douglas debate | 55 |
| Illinois university or its city | 31 |
| Illinois village | 16 |
| Illinois's junior senator | 29 |
| Illinois's nickname | 23 |
| Illinois, "___ of Lincoln" | 36 |
| Illinois, Indiana, Iowa, Michigan, Michigan State, Minnesota, Northwestern, Ohio State, Penn State, Purdue and Wisconsin | 120 |
| Illinois, Wisconsin, etc. | 25 |
| Illinois-based brewery | 22 |
| Illinois-based equipment giant | 30 |
| Illinois-based food giant | 25 |
| Illinoisan in the news | 22 |
| Illiteracy | 10 |
| Illiterate | 10 |
| Illiterate signatory, perhaps | 29 |
| Illiterate signature | 20 |
| Illiterate signing | 18 |
| Illiterates' marks | 22 |
| Illiterates' signatures | 27 |
| Illness | 7 |
| Illness caused by eating Cheetos? | 33 |
| Illness caused by plasmodia | 27 |
| Illness found by a spot check? | 30 |
| Illness in Iberville | 20 |
| Illness indicator | 17 |
| Illness of unknown origin | 25 |
| Illness suffix | 14 |
| Illness that is a swell time? | 29 |
| Illness transmitted from Little Miss Muffet | 43 |
| Illness's end? | 18 |
| Illnesses | 9 |
| Illogical | 9 |
| Illogical person | 16 |
| Illogical, as reasoning | 23 |
| Illogically afraid | 18 |
| Illogically, not the eighth mo. | 31 |
| Ills | 4 |
| Ills in tales | 13 |
| Illum. | 6 |
| Illum. devices | 14 |
| Illuminant | 10 |
| Illuminant gas | 14 |
| Illuminant: Abbr. | 17 |
| Illuminate | 10 |
| Illuminate, with "on" | 31 |
| Illuminated | 11 |
| Illuminated like 1890s streets | 31 |
| Illuminated again | 17 |
| Illuminated by a flame | 22 |
| Illuminated from above | 22 |
| Illuminated from behind | 23 |
| Illuminated from below | 22 |
| Illuminated in a way | 20 |
| Illuminated indirectly | 22 |
| Illuminated like 1890s streets | 30 |
| Illuminated naturally | 21 |
| Illuminated notices above theater doors | 39 |
| Illuminated radio studio sign | 29 |
| Illuminated sign | 16 |
| Illuminated sign in a radio station | 35 |