By NATE SILVER
Elections with results as dramatic as those of Tuesday night are sometimes referred to as “
realigning elections.” The term — although somewhat ambiguous and overused — usually refers to a case in which one or another party not only gains a significant amount of power, but also, in which coalitions are shifted, the signature of which is usually that the rising party performs particularly well in certain geographic regions or among certain demographic groups.
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Rather than a realigning election, then, 2010 served as more of an aligning election: congressional districts behaved less independently from one another, and incumbency status mattered less. Instead, they hewed tightly to national trends and the overall partisanship of each district. Most of the incumbent congressmen whose districts had been outliers before (mainly Democrats like Representative Gene Taylor, whose district gave just 31 percent of its vote to Barack Obama, but also a couple of Republicans like Representative Joseph Cao) were forced into early retirement.
What does this mean for 2012? Democrats — if they are expecting to do better in 2012 than they did this time around — might actually be pleased that elections have become so strongly aligned to partisan orientation. They now have just 12 seats in which Mr. Obama won a minority of the vote to defend — whereas Republicans have 55 where he took the the majority instead. So if there is even a fairly modest shift back to Democrats in 2012, and the shift is again fairly uniform, they could be in a position to achieve quite a few gains.
Or, if the economy improves and — having facilitated a more even balance of power in Washington — the electorate becomes somewhat less angsty, the incumbent advantage could become stronger again, and the gains that Republicans made could prove to be relatively “sticky” — as they were, for instance, after 1994. Plus, Republican inroads in governorships and statehouses on Tuesday night should give them more leverage over redistricting, so they’ll be able to protect a few of their incumbents who otherwise might have lost.
But generally it seems like we have entered a period in which races for Congress have become highly nationalized, and in which few potentially competitive races are conceded by either party and few incumbents are given a free pass. That could mean we’ll continue to see some wild swings over the next several election cycles.