Back when pundits were tripping over themselves to call 2010 an “anti-incumbent” year or an “anti-Establishment” year, conveniently eliding the distinction as it served their purposes, I wrote:
I would be very surprised if any “anti-incumbent fervor” put much dent in the extraordinarily high rates at which incumbents are reelected.
And then I forecast that among House incumbents running for the general election, 87% would win. Commenter treetop noted last week that my prediction was good. Our data suggest at this moment that 86% of House incumbents won their general election bids. Here’s a graph with data from 1972-2010.
Clearly, incumbents did a little worse in 2010 relative to other years, although 1974 is similar (89%). So I wouldn’t be surprised if some breathless commentator is already declaring that OMG THIS WAS THE MOST ANTI-INCUMBENT ELECTION IN ALMOST 40 YEARS.
Me, I’m still pretty impressed by 87%.
But perhaps incumbents won by slimmer margins? Not really. The median percent of the two-party vote won by incumbents was very much in line with the historical average since 1972: 65% in 2010, compared to 68% overall.
And here’s another interesting thing. You might think that lots of incumbents decided not to run or lost their primary races in 2010. I calculated the percent of races with no incumbent running in the general election and it was an astonishing…10%. Which was really no different than most recent elections. Here again is a graph:
There might be other ways you could prove that incumbents had a harder time in 2010. As Brendan Nyhan has shown, Democratic incumbents in competitive districts were more likely to face quality challengers. But that suggests how the climate in 2010 was disadvantageous to Democrats, not to incumbents as a whole.
What is the bottom line? Don’t read too much into a few isolated early primaries (see: Robert Bennett) or into polls where vast majorities of Americans disapprove of Congress or even indicate their willingness to vote for the challenger.
Incumbents still dominate congressional elections.