I.  Purpose
This formula's intent is to give a general sense of how the presidential elections would turn out if the elections were held today.  As we move closer to election day, its usefulness as a prediction tool will increase.

II.  Objectivity
In developing the formula, I made every effort to be objective, rather than biased toward the GOP. Yes, I am Republican, but this formula does not, in any way, falsely inflate the GOP's standing.

III.  Polls
I try to be thorough and objective in gathering polling data.  I mostly use the Polling Report and RealClearPolitics for national polls and DC Political Report and RealClearPolitics for state polls.  However, there may be times when I overlook a poll.  If this happens, I urge my readers to alert me to such polls so that I can include them in the projections.

I.  Adjusted National Polling Data
Up to ten national polls are used to compute an average national margin between John McCain and Barack Obama.  Only polls two weeks old or less will be used.  The average national margin is then subtracted from the national 2004 result to arrive at the national polling data adjustment.  This adjustment is then added to the 2004 margin in each state, yielding the national polling factor for the state.

II.  State Polling Data
The aggregate average of polling data is used in the following manner:

• At most, seven polls from a state are used.
• In the interest of currency, if there is a poll or polls that were conducted less than 15 days prior to the update, then only such polls will be used.  For example, if a poll was conducted in Ohio a week before the update, and another was conducted three weeks before, only the newest poll will be used.
• However, if the latest polls were conducted more than 15 days prior, they will be used.
• In no case will a poll over 30 days old be used.

III.  Combining state and national polling factors
The state and national polling factors are combined to produce the state's Election Projection.  For the purposes of this calculation, the national polling factor is viewed as simply another state poll.  Therefore, if only one state poll is used, the national polling factor contributes 50% of the formula weight.  If two state polls are used, the national factor is reduced to 33%.  Three state polls reduce it to 25% and so on.  The idea here is that the more state polls have been released, the more accurate they should be and the less weight needs be placed on a national polling component.

The formula:

  ((State Polling * No. state polls) + Nat. Polling) / (No. state polls + 1)

Here is an example of the calculations using the formula for Ohio (2008 numbers are from June 1):

• 2004 National Result:  Bush +2.46%
• 2008 National Polling:  Obama +3.64%
• National Polling Adjustment:  Obama +6.10%
• 2004 Ohio Result:  Bush +2.10%
• 2008 Ohio Polling (3 polls):  Obama +1.33%
• Weight:  State polls = 75%, National polls = 25%
• Projected 2008 National Result: Obama 51.54%, McCain 47.46%
     NOTE:  One percent is allocated to any third-party candidates.
• Projected 2008 Ohio Result: Obama wins by 2.00%

I.  Head-to-head Polling
The aggregate average of polling data is used in the following manner:

• At most, seven polls from a state are used.
• In the interest of currency, if there is a poll or polls that were conducted less than 15 days prior to the update, then only such polls will be used.  For example, if a poll was conducted in Ohio a week before the update, and another was conducted three weeks before, only the newest poll will be used.
• However, if the latest polls were conducted more than 15 days prior, they will be used.
• In the event that no poll has been released in the prior 30 days, a poll over 30 days old can be used.

II.  Incumbent Job Approval
The last job approval numbers provided by Survey USA will used for this component.  Obviously, this factor is more relevant when the incumbent is seeking re-election.  So, the weight of this factor will be 15% if the incumbent is seeking re-election and 5% if not.

The formula for incumbents:

  (Head-to-head Polling * 85%) + (Job Approval * 15%)

The formula for open seat races:

  (Head-to-head Polling * 95%) + (Job Approval * 5%)

Here is an example of the calculations using the formula for the Indiana gubernatorial race (numbers are from June 1):

• Head-to-head Polling:  Mitch Daniels (R) +7.4%
• Job Approval:  Daniels -3%
• Projected Result: Daniels defeats Thompson by 5.8%

The formula for contested House races is substantially unlike the formulas I described above.  There are four main differences between this formula and the one used for Senate and gubernatorial races.  First, since job approval numbers for House members are extremely difficult to track, there is not a job approval component to the formula.

Second, published polls for district races are also much more difficult to find than for Senate or gubernatorial races, so I needed another metric which would be reliable and consistent throughout the election season.  The aggregate race ratings of four well-known pundits is that metric.  The predictions of Stuart Rothenberg, Charlie Cook, Larry Sabato, and the Congressional Quarterly will be used.  Since their predictions are qualitative (i.e. leans, toss-up, solid, etc), I will assign a margin of victory to them as follows:

Third, when polling data can be obtained, their weight be will based on whether one poll or multiple polls are available.  If one poll is available, it will get a 25% chunk of the projection.  If two polls have been published, the average will be taken, and that result will be 50% of the projection.  Currency stipulations posted in the Senate and gubernatorial formula explanation will apply here as well.

Finally, partisan polls will be used with a caveat.  The results will be adjusted by subtracting 3 points from the party of the pollster and adding them to the other party.  For example, if a Republican polling firm publishes a poll with the GOP candidate winning 54% to 40%, the poll will be entered into the calculations as 51% to 43%.

For races with no published polls:

Pundit Avg. * 100%
   NOTE:  Because I refuse to post a "toss-up" rating on any race, I will decide one way or the other in the event that pundit predictions result in a tie.  The margin for such races will be +0.5% for my best guess.

For races with one published polls:

(Pundit Avg. * 0.75) + (Poll * 0.25)

For races with two published polls:

(Pundit Avg. * 0.50) + (Poll * 0.50)

Here is an example of the calculations using the formula for the California District 11 race (numbers are from June 1, positive numbers favor incumbent party):

• Pundit Predictions:  Factor = 2.0 for incumbent McNerney
  • Stuart Rothenberg:  Toss-up
  • Charlie Cook:  Toss-up
  • Larry Sabato:  McNerney by 4% (leans DEM)
  • Congressional Quarterly:  McNerney by 4% (leans DEM)
• Polls:  Factor = 4.0 for challenger Andal
  • Benneson Strategy (D):  McNerney(D) 42%, Andal(R) 40%
• Projected Result:  (2.0 * 0.75) + (-4.0 * 0.25) = 0.5%
  • McNerney defeats Andal by 0.5%