I started thinking about this piece yesterday between Jim Geraghty’s NRO Campaign Spot piece (retweeted by fellow moron @ComradeArthur) with regards to the percentage breakdown of the electorate. It’s been somewhat overwridden by Jay Cost’s great blog post this morning but still I think it’s worth reviewing a national point they’ve skirted past.
Take a look at this handy chart the Washington Post produced in 2007. It captures the percent of the electorate showing up as Democrats, Republicans, and Independents. Focus on the Independents column.
What you’ll note in looking at that column is that for every presidential election since 1980 either 26 or 27% of the electorate has been independent. 2008 was similar (scroll down to the 15th break-out), but an outlier(or the start of a new trend? History will tell us); Independents comprised 29% of voters in exit polls last time around. Now, this includes the somewhat troubled 2000 and 2004 exit polls which were below par at a state level in predicting the overall winner. Nonetheless it gives us a good starting point for estimating the size of the Independent share nationally. And I say nationally because your mileage will definitely vary looking at state to state numbers.
So one would expect, based on history, to see 25 to 29% of the electorate being Independents in a Presidential election (and that margin is being generous, since the last time we saw the Independent percentage outside 26 to 29% for a Presidential election was in 1976, a hard year to self-identify as a Republican). Which means that 71 to 75% are partisans.
The split there is a stickier wicket. Which is for a future post.