Number Crunching, September Edition

With 6 weeks to go until Election Day, Nate Silver runs the numbers on September poll leads and finds with the exceptions of "Dewey beats Truman!" and the Supremes screwing over Al Gore, the poll average leader at the 45 day mark went on to win 17 of the last 19 Presidential races.

Our polling database contains surveys going back to 1936. The data is quite thin (essentially just the Gallup national poll and nothing else) through about 1968, but it’s nevertheless worth a look.

In the table below, I’ve averaged the polls that were conducted 40 to 50 days before the election in each year — the time period that we find ourselves in now. (In years when there were no polls in this precise time window, I used the nearest available survey.)

The table considers the race from the standpoint of the incumbent party (designated with the color purple) and the challenging party (wearing the orange jerseys), without worrying about whether they were Democrats or Republicans. Mr. Obama’s position, for instance, is probably more analogous to that of the Republican incumbent George W. Bush in 2004 than it is to the candidate from his own party that year, John Kerry.


 

As you can see, President Obama's nearly 4 point lead is a larger one than he had in 2008.  It is however the smallest of the incumbent leads of a winner since FDR in 1944.  Six weeks is still enough to win, but by this point, the race appears to be very much decided.

At this point serious attention needs to be paid to shoring up the down ballot races as motivation to get people to the polls.  We'll see what happens.