District lines change every ten years. I notice that the 3rd and 4th have elected Republicans more recently than 1904, though I don’t know what the borders of the district were at the time.
I took into account said district line changes. What was the 3rd and 4th in 2015 were not in decades past. The 3rd district heritage I followed back from the present:
3rd (1993-present)
5th (1949-1993)
4th (1903-1949)
It was in 1904 when the last Republican was elected from the historical incarnation of the present 3rd (although you can have overlapping portions that may have done so more recently).
The Republicans you cited that were elected to the 3rd and 4th (as then-numbered) were in 1972 (Robert Hanrahan) and 1986 (Jack Davis). The Hanrahan 3rd district was merged with the 5th in 1992 (Dem Marty Russo, who beat Hanrahan in 1974 held the district until 1992 when he lost the primary to ex-5th district member Bill Lipinski). So you can say part of the current 3rd did elect a Republican as recently as 1972. However, Hanrahan’s former home is entirely now within the present 2nd (as is Russo’s).
With respect to Republican Jack Davis in the old 4th, he was defeated by Dem George Sangmeister in 1988 and that became the 11th in 1992. Sangmeister was defeated by Republican Jerry Weller. That’s currently the 16th district held by Adam Kinzinger. However, Davis’s home in New Lenox is presently in Democrat Bill Foster’s 11th district and the late Sangmeister’s home in Mokena is entirely within Bobby Rush’s 1st district.
It’s not an exact science following the lines and their histories, especially given that all IL districts have been considerably augmented over the years. It once had 26 Congressional districts and 2 additional At-Large seats and has since lost 10 districts. You’d have to do research down to the individual precincts to ascertain when districts voted for one party or another.
As an aside, long ago when Chicago didn’t exist (still Fort Dearborn), that entire area was a part of way-south Edwards County at the time my GGG-grandfather’s father-in-law was its premier political figure in the 1810s.