The incumbent 50% rule

Interesting article pointing out that Bush is actually dead even with Kerry when you apply the incumbent rule:

But is it really possible for Kerry to close a 5-point gap, absent some fundamental change in voter preference? To find historical precedent, we must reach back in history all the way to 1996, the most recent incumbent presidential election. Bill Clinton averaged 51 percent in the final polls but received 49 percent on election day, while Bob Dole averaged 37 percent but received 41 percent – a net shift of 6 points. Not only can Kerry close such a gap, it is extremely likely that he will.

There have been four incumbent presidential elections in the past quarter-century. If we take an average of the final surveys conducted by the three major networks and their partners, we find that in three of these the incumbent fell short of or merely matched his final poll number, while exceeding it only once, and then by just a single point (Ronald Reagan). On average, the incumbent comes in half a point below his final poll result.

Year Incumbent Final Polls (in percent) Actual Vote (in percent)
1996 Bill Clinton 51 49
1992 George Bush Senior 37 37
1984 Ronald Reagan 58 59
1980 Jimmy Carter 42 41

The numbers for challengers look quite different. In every case, the challenger(s) – I include Ross Perot in 1992 and 1996 – exceed their final poll result by at least 2 points, and the average gain is 4 points. In 1980, Ronald Reagan received 51 percent, fully 6 percentage points above his final poll results.

In other words, watch Bush’s number, not Kerry’s. If he can’t break 50 he’s toast.

How about this, from Zogby?

The post convention bounce for Bush is over and his biggest hurdle is among undecided voters who give him a 31 percent positive job performance rating and a 69 percent negative rating. Only 13 percent of undecided voters feel that the president deserves re-election (his lowest yet) while 37 percent feel it is time for someone new. Undecideds at 8 percent are high because we don’t push them until later. Five points of these are hard undecideds, two-points use to be with Kerry, and one point with Bush. How will they break in the end? Will they even vote?

There’s a chance that they won’t be able to disenfranchise enough voters this time around…