| Election Name: | 2008 Illinois Republican presidential primary |
| Country: | Illinois |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 2004 Illinois Republican presidential primary |
| Previous Year: | 2004 |
| Next Election: | 2012 Illinois Republican presidential primary |
| Next Year: | 2012 |
| Candidate1: | John McCain |
| Color1: | ce5c17 |
| Home State1: | Arizona |
| Delegate Count1: | 54 |
| Popular Vote1: | 426,777 |
| Percentage1: | 47.45% |
| Color2: | 85bb65 |
| Candidate2: | Mitt Romney |
| Home State2: | Massachusetts |
| Delegate Count2: | 3 |
| Popular Vote2: | 257,265 |
| Percentage2: | 28.60% |
| Color4: | 990000 |
| Candidate4: | Mike Huckabee |
| Home State4: | Arkansas |
| Delegate Count4: | 0 |
| Popular Vote4: | 148,053 |
| Percentage4: | 16.46% |
| Candidate5: | Ron Paul |
| Color5: | fed105 |
| Home State5: | Texas |
| Delegate Count5: | 0 |
| Popular Vote5: | 45,055 |
| Percentage5: | 5.01% |
| Map Size: | 150px |
| Outgoing Members: | GA |
| Elected Members: | MA |
| Votes For Election: | 70 delegates to the Republican National Convention (57 pledged, 13 unpledged) |
The 2008 Illinois Republican presidential primary was held on February 5, 2008. Illinois was one of 24 States holding a primary or caucus on Super Tuesday, 2008. Delegates from each of Illinois' 19 congressional districts are selected by direct election. In addition, the primary ballot also contains a preference poll that lists the presidential candidates. 10 at-large delegates and 3 party leader delegates were elected at the State Convention and officially went to the Republican Convention unpledged.
| Candidate | Votes | Percentage | Delegates | |
|---|---|---|---|---|
| John McCain | 426,777 | 47.45% | 54 | |
| 257,265 | 28.60% | 3 | ||
| 148,053 | 16.46% | 0 | ||
| 45,055 | 5.01% | 0 | ||
| Rudy Giuliani | 11,837 | 1.32% | 0 | |
| Fred Thompson | 7,259 | 0.81% | 0 | |
| 2,318 | 0.26% | 0 | ||
| Jim Mitchell, Jr. | 483 | 0.05% | 0 | |
| Tom Tancredo | 375 | 0.04% | 0 | |
| Total | 899,422 | 100% | 57 |