Joni Ernst won with 51.7% of the vote (864,997 votes), ahead of Theresa Greenfield with 45.1% (754,859 votes).
The margin between the first two candidates was 6.6 percentage points (110,138 votes). The party margin (Republican share minus Democratic share) was a Republican lead of 6.6 points.
Compared with the previous comparable race in the same area, the party margin moved 17.8 points toward Democrats.
1,671,828 votes were counted in this race, for 4 candidates or options.
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