Issue 2 lost after a fight that pitted voter advocacy groups and unions against business interests and the Ohio Republican Party. Lawyers' groups split on the issue.
The constitutional amendment would have created a 12-member citizen commission to redraw Ohio's political districts every decade. It was prompted by discontent over the maps approved by the state Legislature in 2011.
Tuesday's vote leaves U.S. House maps in the hands of the state Legislature, and legislative districts in the hands of the five-member Ohio Apportionment Board.
In conceding the race, proponents highlighted common ground identified during the campaign. They said all agree Ohio's redistricting system is broken and sides should come together before 2022 to fix it.