… But here’s one such theory, as described by a New York Times article published Sunday: Perhaps Cantor’s defeat — and the near-defeat of Republican Sen. Thad Cochran in Mississippi — has something to do with migration patterns. If more people are moving into areas where they are less familiar with the incumbent, perhaps the incumbency advantage has waned.
Indeed, there’s robust evidence that politics are becoming more nationalized; state and local races (like those for governor) are more likely to follow patterns from federal races and less likely to involve ticket-splitting.
But it’s less clear that this has much to do with migration patterns, or at least not in the way that The New York Times proposes. More of the evidence contradicts rather than supports its hypothesis, in fact. CONT.
Nate Silver, FiveThirtyEight