No politics is local anymore and it’s driving us apart, according to a new mathematical model of political competitiveness developed by Mattias Polborn, professor of economics at Vanderbilt University, and Stefan Krasa, professor of economics at the University of Illinois. Their paper, “Political Competition in Legislative Elections,” appears in the American Political Science Review.
This new model represents the fundamental competitive forces in legislative elections as they unfold today, and is the first to consider the impact of outside elections on voters’ choices. It also helps explain how gerrymandering contributes to polarization—even in non-gerrymandered districts.
Voters care about all elections, not just theirs
The most popular way of thinking about electoral politics—known as the median voter theory—goes that elections should always be a fight for the moderates, because candidates are unlikely to draw more partisan voters to the other side.
The problem is that the median voter theory has not accurately described the state of U.S. legislative elections for the past 40 years. We are much more polarized than we used to be—or should be, according to that theory.
The flaw, the researchers surmised, is that the median voter theory assumes that voters are only interested in the election they themselves are voting in—that their only concern is which of their district’s candidates best reflects their own views. However, as anyone who has watched a local campaign ad featuring House Minority Leader Nancy Pelosi or President Donald Trump can attest, that’s not how voters think anymore.
“What we point out in this paper is that in many elections they are effectively linked across the country,” Polborn said. Today’s voters also care a lot about how their votes will affect the overall balance of power between the parties in the legislature—sometimes more than they care about their district’s candidates themselves.
For example, a moderately conservative voter might actually have more policy preferences in common…
