Chuck Grassley won with 56.0% of the vote (681,501 votes), ahead of Michael Franken with 43.8% (533,330 votes).
The margin between the first two candidates was 12.2 percentage points (148,171 votes). The party margin (Republican share minus Democratic share) was a Republican lead of 12.2 points.
Compared with the previous comparable race in the same area, the party margin moved 5.6 points toward Republicans.
1,216,646 votes were counted in this race, for 2 candidates or options.
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