The piece deserves to be read in its entirety, but the nut of it is Issenberg’s account of the evolving understanding of why midterms have come to differ so much from presidential-year elections. Until not so long ago, the common assumption was that midterms often favored the party not holding the White House because many swing voters who had voted for the president found themselves disillusioned and wanted to issue a rebuke… But the swing-voters dynamic has been greatly overstated—even in the historic midterm “rebuke” sweep of 2010, fewer than six percent of 2008 voters went for the opposite party in their congressional vote two years later.
The CW about 2010 was that Barack Obama’s performance in office disappointed vast numbers of 2008 supporters who believed his talk of bipartisanship and “Red, White and Blue America” and tilted to the GOP in the midterms to rebuke him or restrain him and his “overreaching” party—a phenomenon strengthened by the advent of a new citizens movement called the Tea Party which emerged from the ranks of independents unhappy with both parties.
A “swing” of six percent of 2008 voters can hardly sustain this narrative of triumph and betrayal, can it?
No it cannot. Demography and turnout make all the difference. And the US midterms are increasingly more a survey of the white and the over-60s than of the general population. Which is why extrapolating from them too much is a fatal error, but one that Republicans seem to make every time. It’s a short term tonic for a long-term problem. And it can make the long-term problem worse.