Following the 2010 census, congressional seats have been reapportioned, and new district lines have been drawn.
First, the number of competitive House of Representatives seats drawn in the new maps has dropped slightly from the old maps and dramatically over the past four decades. There are 101 competitive seats for the decade of the 2010s. There were 103 in the 2000s, 129 in the 1990s, 135 in the 1980s, and 152 in the 1970s.
Research has shown that redistricting itself is not the sole or even the major cause of party polarization in the United States. But with the drawing of new lines in 2012, the Bipartisan Policy Center sees that over the next decade there will likely be more polarization of votes along party lines, and there will be fewer House seats that turn over from one party to the other.
Read the press release here.
Read the 2012 Voter Registration report here.
Read the 2012 Voter Turnout report here.