How Accurate Was the Obama Delegate Prediction Spreadsheet?


On February 7, an internal Obama campaign spreadsheet leaked in the press. It contained the campaign’s predictions for all of the remaining primaries. Now that the primaries are over, we have the opportunity to judge the accuracy of Obama’s prognosticators, who, as everyone knows by now, showed remarkable prescience in their planning this campaign season.

Below are the spreadsheet’s popular vote and delegate predictions compared to actual results. The numbers show that the Obama campaign strategists were routinely too conservative: they underpredicted both the margins of their victories and their losses. They often anticipated a close to 50-50 split in a state that turned out to seriously favor one of the two candidates.

Of the states they predicted correctly, they underpredicted their margin of victory (aka were too pessimistic) in 16 states and underpredicted their margin of loss (aka were too optimistic) in six. They only overpredicted their margin of victory in two states, and never overpredicted a loss. In total, they got 24 of the 27 primaries after February 5th correct.

Of the ones the campaign got wrong, they were too hopeful in South Dakota and Indiana, where they predicted victories but suffered losses, and were too pessimistic in Maine, where they predicted a close loss but actually saw a substantial victory.

They nailed the delegate count exactly in five states, and were within one delegate in five more. They predicted their delegate count to within five delegates in 23 of the 27 primaries.

Louisiana Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 54% 44% 31 25
Results 57% 36% 34 22
Difference +3% -8% +3 -3

Nebraska Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 60% 40% 15 9
Results 68% 32% 16 8
Difference +8% -8% +1 -1

Virgin Islands Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 60% 40% 2 1
Results 90% 8% 3 0
Difference +30% -32% +1 -1

Washington Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 60% 40% 49 29
Results 50% 47% 52 26
Difference -10% +7% +4 -3

Washington’s numbers are complicated by the fact that the state held both a primary and a caucus.

Maine Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 49% 51% 10 14
Results 59% 40% 15 9
Difference +10% -11% +5 -5

Democrats Abroad Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 60% 40% 5 2
Results 67% 33% 4.5 2.5
Difference +7% -7% -0.5 +0.5

Washington DC Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 58% 42% 9 6
Results 75% 24% 12 3
Difference +17% -18% +3 -3

Maryland Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 53% 46% 37 33
Results 61% 36% 42 28
Difference +8% -10% +5 -5

Virginia Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 50% 48% 43 40
Results 64% 36% 54 29
Difference +14% -12% +11 -11

Hawaii Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 52% 47% 11 9
Results 76% 24% 14 6
Difference +24% -23% +3 -3

Wisconsin Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 53% 46% 40 34
Results 58% 41% 42 32
Difference +5% -5% +2 -2

Ohio Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 46% 53% 68 73
Results 44% 54% 66 75
Difference -2% +2% -2 +2

Rhode Island Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 42% 57% 8 13
Results 40% 58% 8 13
Difference -2% +1% 0 0

Texas primary Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 47% 51% 92 101
Results 47% 51% 99 94
Difference 0% 0% +7 -7

Texas’s numbers are complicated by the fact that the state held both a primary and a caucus.

Vermont Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 55% 44% 9 6
Results 59% 39% 9 6
Difference +4% -5% 0 0

Wyoming Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 60% 40% 7 5
Results 61% 38% 7 5
Difference +1% -2% 0 0

Mississippi Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 62% 38% 20 13
Results 61% 37% 19 14
Difference -1% -1% -1 +1

Pennsylvania Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 47% 52% 75 83
Results 45% 55% 73 85
Difference -2% +3% -2 +2

Guam Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 55% 44% 2 2
Results 50% 50% 2 2
Difference -5% +6% 0 0

Indiana Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 53% 46% 39 33
Results 49% 51% 34 38
Difference -4% +5% -5 +5

North Carolina Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 53% 45% 61 54
Results 56% 41% 66 49
Difference +3% -4% +5 -5

West Virginia Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 43% 55% 13 15
Results 25% 67% 8 20
Difference -18% +12% -5 +5

Kentucky Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 42% 56% 23 28
Results 30% 66% 14 37
Difference -12% +10% -7 +9

Oregon Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 52% 47% 28 24
Results 59% 41% 31 21
Difference +7% -6% +3 -3

Puerto Rico Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 45% 54% 25 30
Results 32% 68% 17 38
Difference -13% +13% -8 +8

Montana Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 55% 44% 9 7
Results 56% 41% 9 7
Difference +1% -3% 0 0

South Dakota Obama Pop. Vote Clinton Pop. Vote Obama Del. Clinton Del.
Prediction 57% 42% 8 7
Results 45% 55% 7 8
Difference -12% +13% -1 +1

All results numbers, both popular vote percentages and delegate counts, come from the New York Times.