Undecideds vote for the incumbent 70% of the time?
A friend of mine asked me if it’s true that “undecideds vote for the incumbent 70% of the time.” Here’s what the Cook Report had to say::
[U]ndecided voters historically have broken heavily against well-known, well-defined incumbents. This has proven true on the congressional, senatorial, gubernatorial and presidential level. That’s the origin of the phrase in politics for incumbents, “what you see is what you get” — you get pretty much the percentage on Election Day that the last round of polls indicate that you will get, while the undecided vote goes elsewhere.
So I guess not, but I guess I should check with the NES dataset.
Comments
Kaufman, Petrocik & Shaw argue that the conventional wisdom Cook is spouting is simply not true. Their NES analysis shows that:
—On average, undecided voters voted challenger 34%, incumbent 35%, other 7% (Perot in 1992, mostly), and didn’t vote 25%.
—On average, those who decided their vote in the last week voted challenger 42%, incumbent 48%, other 10%.
(Numbers from elections with incumbents running; they shift a couple points in the challenger party’s favor over all elections, but that’s likely capturing some ‘fatigue’ effect on the presidential level.)
Posted by: Matt Jarvis | October 7, 2008 04:49 PM
It appears to me that if the undecided vote is divided roughly 50-50 then the results of the last polls will mirror the election results provided the undecided are a small percentage of the total vote.
You got two trucks full of grain, adding a few grains to each truck is not going to affect the total in each truck very much even if a few more grains are added to one.
Posted by: Vader | October 8, 2008 10:46 AM
My understanding was that voters who were genuinely undecided when they entered the voting booth would break heavily towards the challenger. The idea was that a genuinely undecided voter had not been persuaded to vote for the incument. If an incumbent, with all the advantages of a term in office and a bully pulpit, can’t close the deal with that voter, the voter is essentially going to vote for a change.
So what did I miss? What did Kaufman and team see otherwise?
Posted by: dork matter | October 9, 2008 03:48 PM