2018Final results
2018 election for Missouri House District 121
Missouri House of Representatives · Missouri
Don Mayhew (R) won with 69.3% of the vote, defeating Matt Heltz (D) by 38.6 points.
Don MayhewRepublican · winner
69.3%7,996
Matt HeltzDemocrat
30.7%3,544
11,540 votes
Source: MIT Election Data and Science LabUpdated Oct 1, 2026, 6:17 AM ET
The seat over time
D − R margin in this seat's races around 2018
Races before and after
Source: MIT Election Data and Science LabUpdated Oct 1, 2026, 6:17 AM ET