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Where are undecideds falling?

November 2nd, 2012, 4:30pm by Sam Wang

(original version published on temporary site with comment thread)

In the home stretch to Tuesday, undecided voters are claimed to be an unknown that could increase President Obama’s lead – or turn the race around for Governor Romney. But many pundits (and comedians) don’t understand what it means to be “undecided.” Most undecideds probably have a preference, but are unable or unwilling to state it. Now they are starting to do so.

There is a myth that undecided voters start in the middle, from where they make a decision to support a specific candidate. As my colleague Josh Gold and I have written (The Undecided Voter’s Secret Ballot, New York Times, October 28, 2008), decisions are not like that. We are not always aware of our mental commitments, even if we have already made them. Instead, think of “candidate-preference” and “ability-to-report” as distinct qualities, analogous to how hair color and height are unrelated to one another.

Let’s look at the largest single shock to the 2012 race, Debate #1. In a single day, Romney closed nearly the entire 6-point gap (measured in Popular Vote Meta-Margin) between him and President Obama. What happened to undecided voters?
Here is an average calculated from 98 national polls from our data partners at, unpacked on a day-by-day basis:

The overall picture is of undecideds gradually diminishing by about 1.0% over the month of October. There might be a small hiccup of around 1% around October 4th, the day after the debate. But the key point is that there is no lasting decrease in undecideds that corresponds to the jump in the Obama-Romney margin.

Indeed, there is a very faint tendency for the two-candidate margin to go upward over the last 3 weeks – about 0.5%. Undecideds could be discovering their inner Democrat. Or decided voters could be flipping, which seems possible if one looks at the RAND survey since October 8th:

(Incidentally, the Shifts-Between-Candidates graph is the only graph at RAND I follow. It follows specific voters, so we can see them flow back and forth. I don’t regard RAND’s Election Forecast as any better than other pollsters. It might be worse; the size of their popular vote margin is certainly not looking very persuasive to me at the moment.)

In any event, there’s little evidence to say that undecideds are breaking in a big way. Note that they are also not “independents,” which are a different beast. Most independents have a distinct preference for a candidate, but not a party. Charles Franklin has analyzed undecideds and finds that they break nearly equally.

Which brings me to a major point. We fuss and mock undecided voters – but isn’t the elephant in the room the decided voters? They can vary in enthusiasm, which affects how they show up in likely-voter screens. Or they can flip, as one can see in the RAND data. Think about that. The electorate is so polarized this year. If they go right from Obama to Romney, or vice versa, they evidently don’t stop at “undecided” along the way. These flighty people, not “undecideds,” are the ones that the campaigns should be targeting in the home stretch.

Tags: 2012 Election · President

3 Comments so far ↓

  • Matt

    Sam, thanks for posting on this subject. Until now, I haven’t heard anything on how undecideds behave or may break other than old, conventional wisdom takes. I really appreciate RAND’s chart. Though I agree that their polls may or may not be the most accurate, it’s still worth having at least one data point on where undecideds are going.

  • Ms. Jay Sheckley

    “isn’t the elephant in the room the decided voters?”
    ::gasp!:: OMG!
    I wonder what can be done… I’m trying to get out the word about this site and any other truth I can illuminate. Maybe I better get on the phones.
    Speaking of phones and such, my stellar niece Hannah R, a Princeton sophomore, is down in Florida this week, working on the election. I hope somebody brings the kids donuts

  • Ed

    A question; how are these group of undecided voters identified. I acknowledge that independents register as such; however, how is this group, that receives so much attention, identified so as to possibly generate changes in the election?

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