… Despite high reelection rates, in recent years the incumbency advantage has declined sharply: by 50 percent or more in most estimates. …
Two culprits seem to bear the blame in the case of the vanishing incumbency advantage (to play off the title of perhaps the most famous paper ever written on congressional elections, “The Case of the Vanishing Marginals” by one of my former teachers, professor David Mayhew, who was honored at a conference last week): partisanship and money. [cont.]
Mark Mellman (Mellman Group), The Hill