1970Final results
1970 election for Missouri House District 78
Missouri House of Representatives · Missouri
Hardin Cox (D) won with 62.0% of the vote, defeating John C. Costello (R) by 23.9 points.
Hardin CoxDemocrat · winner · incumbent
62.0%6,184
John C. CostelloRepublican
38.0%3,795
9,979 votes
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET
The seat over time
D − R margin in this seat's races around 1970
Races before and after
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET