There is a political science literature that gerrymandering, as an empirical matter, has had less effect on American politics than the pundits like to claim. There is little past evidence that gerrymandering leads to more polarization or less competitive elections. The U.S. Senate provides perhaps conclusive evidence about polarization: you cannot gerrymander state boundaries, but the Senate is just as polarized as the House. Politicians are polarized because the U.S. now has polarized ideological political parties.
Still, it is hard for me to reject the hypothesis that gerrymandering is very important. Why is that? Well, two things:
- California: it moved to nonpartisan districting, and Democrats pulled out a two-thirds supermajority. Of course, there could be other explanations: nonpartisan primaries, continuing Mexican-American population growth and leftward shifts in public opinion. It certainly seems as though the new cleaner districts helped the Democrats pick up Congressional seats;
- The GOP seems to have lost the overall Congressional popular vote, but maintained its majority.
I do not know, but it seems as though gerrymandering may have made a very large difference in this election. What does the literature say? Anyone?