Tom Harkin won with 54.5% of the vote (535,975 votes), ahead of Thomas J. Tauke with 45.4% (446,869 votes).
The margin between the first two candidates was 9.1 percentage points (89,106 votes). The party margin (Republican share minus Democratic share) was a Democratic lead of 9.1 points.
Compared with the previous comparable race in the same area, the party margin moved 41.5 points toward Democrats. The winning party changed.
983,933 votes were counted in this race, for 2 candidates or options.
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