Majoritarian electoral institutions have been linked to polarization. However, ending gerrymandering practices in redistricting cannot correct for increased polarization due to the growing percentage of the U.S. electorate living in "landslide counties", counties where the popular vote margin between the Democratic and Republican candidate is 20 percentage points or greater. Of the 92 U.S. House seats ranked by The Cook Political Report as swing seats in 1996 that transitioned to being non-competitive by 2016, only 17 percent came as a result of changes to district boundaries while 83 percent came from natural geographic sorting of the electorate election to election.
