Tom Harkin won with 62.7% of the vote (941,665 votes), ahead of Christopher Reed with 37.3% (560,006 votes).
The margin between the first two candidates was 25.4 percentage points (381,659 votes). The party margin (Republican share minus Democratic share) was a Democratic lead of 25.4 points.
Compared with the previous comparable race in the same area, the party margin moved 67.7 points toward Democrats. The winning party changed.
1,502,918 votes were counted in this race, for 2 candidates or options.
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