Chuck Grassley won with 64.4% of the vote (718,215 votes), ahead of Roxanne Conlin with 33.3% (371,686 votes).
The margin between the first two candidates was 31.0 percentage points (346,529 votes). The party margin (Republican share minus Democratic share) was a Republican lead of 31.0 points.
Compared with the previous comparable race in the same area, the party margin moved 56.4 points toward Republicans. The winning party changed.
1,116,063 votes were counted in this race, for 3 candidates or options.
More races: all races, candidates and analysis.