1984Final results
1984 election for Illinois's 4th District
U.S. House · Illinois
George M. O'Brien (R) won with 64.0% of the vote, defeating Dennis E. Marlow (D) by 28.0 points.
George M. O'BrienRepublican · winner
64.0%121,744
Dennis E. MarlowDemocrat
36.0%68,547
190,291 votes
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
The seat over time
D − R margin in this seat's races around 1984
Races before and after
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
Money in this race
Each line compares the two campaigns on one scale.
No DemocratGeorge M. O'Brien
—
Raised by the campaign
$204.7K
—
Spent by the campaign
$143.9K
—
Cash on hand
$62.7K
Campaign money: FEC, through Dec 31, 1984.
Source: FEC campaign filingsUpdated Dec 31, 1984