Charles E. Grassley won with 53.5% of the vote (683,014 votes), ahead of John Culver with 45.5% (581,545 votes).
The margin between the first two candidates was 7.9 percentage points (101,469 votes). The party margin (Republican share minus Democratic share) was a Republican lead of 7.9 points.
Compared with the previous comparable race in the same area, the party margin moved 4.7 points toward Republicans.
1,276,986 votes were counted in this race, for 5 candidates or options.
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