This really interesting article published by the Center for Politics of the University of Virginia is by J. Miles Coleman. The key points are:

— Though new congressional lines are typically put into effect for election years ending in “-2”, four states adopted new maps at later points during this last decade.

— In North Carolina, Florida, Virginia, and Pennsylvania, Republican-friendly maps were thrown out mid-decade in favor of plans that were more amenable to Democrats.

— If those pro-Republican maps were still in place, there’s a good chance that House Republicans would be in the majority now

Read the full article here here.