History
The Impact of Gerrymandering on Democratic Representation
Quick fact
In the 2012 U.S. House elections, Republican candidates received about 49% of the national popular vote but won 54% of the seats, largely due to gerrymandering. The 'efficiency gap'—a measure of wasted votes—quantifies this distortion, and courts have used it to strike down extreme partisan gerrymanders.
Why this is interesting
You might believe that elections are decided by voters. But sometimes, the outcome is determined long before you cast your ballot—when the district lines are drawn.