Obama holds an 8% lead in the final Wisconsin polling average. In an attempt to try and gauge the solidity of that lead, I produced the following table showing the shift from the final polls to the final results in every state that has held a primary or caucus and featured a pre-election poll in 2008 (all of the final polling averages are my own, published in the nomination at a glance series):
2008 Candidate Performance From Final Polls To Final Results
| State |
Final Poll Margin |
Final Popular Margin |
Shift |
| Iowa |
Obama +2% |
Obama +8% |
Obama +6% |
| New Hampshire |
Obama +7% |
Clinton +2% |
Clinton +9% |
| Nevada |
Clinton +4% |
Clinton +6% |
Clinton +2% |
| South Carolina |
Obama +12% |
Obama +28% |
Obama +16% |
| Florida |
Clinton +22% |
Clinton +17% |
Obama +5% |
| Alabama |
Clinton +1% |
Obama +14% |
Obama +15% |
| Arizona |
Clinton +4% |
Clinton +9% |
Clinton +5% |
| Arkansas |
Clinton +40% |
Clinton +44%% |
Clinton +4% |
| California |
Clinton +2% |
Clinton +9% |
Clinton +7% |
| Colorado |
Obama +2% |
Obama +35% |
Obama +33% |
| Connecticut |
Clinton +4% |
Obama +4% |
Obama +8% |
| Delaware |
Clinton +2% |
Obama +10% |
Obama +12% |
| Georgia |
Obama +16% |
Obama +36% |
Obama +20% |
| Illinois |
Obama +29% |
Obama +32% |
Obama +3% |
| Massachusetts |
Clinton +7% |
Clinton +15% |
Clinton +8% |
| Minnesota |
Clinton +7% |
Obama +34% |
Obama +41% |
| Missouri |
Clinton +4% |
Obama +1% |
Obama +5% |
| New Jersey |
Clinton +7% |
Clinton +10% |
Clinton +3% |
| New Mexico |
Obama +6% |
Clinton +1% |
Clinton +7% |
| New York |
Clinton +17% |
Clinton +17% |
Even |
| Oklahoma |
Clinton +26% |
Clinton +24% |
Obama +2% |
| Tennessee |
Clinton +15% |
Clinton +13% |
Obama +2% |
| Utah |
Obama +24% |
Obama +18% |
Clinton +6% |
| Washington |
Obama +13% |
Obama +37% |
Obama +24% |
| Utah |
Obama +24% |
Obama +18% |
Clinton +6% |
| D.C. |
Obama +36% |
Obama +51% |
Obama +15% |
| Maryland |
Obama +20% |
Obama +23% |
Obama +3% |
| Virginia |
Obama +18% |
Obama +29% |
Obama +11% |
Obama has gained from the final poll to the final result in 17 of the 28 states with pre-election polls, while Clinton has gained in 10 and the margin was perfectly accurate in one more. Generally speaking, the less polled a state was, the older polls of the state were, whether or not there was an ARG poll of the state, and whether or not the state was a caucus appears to be the cause for virtually all of this polling error. Obama wildly outperformed the polls in caucus states such as Colorado, Minnesota and Washington, each of which only had one poll that was more than a week old. However, he also outperformed the polls by double digits in primary states like Alabama, Delaware, D.C., Georgia, South Carolina, and Virginia. By contrast, Clinton has never outperformed the polls by more than 10%, although she did do quite well in California, Massachusetts, New Hampshire, and New Mexico.
Given this data, it appears that a Clinton victory in Wisconsin would be even less likely than her victory in New Hampshire. Obama's lead in Wisconsin is slightly larger than his lead was in New Hampshire, and has been more stable over a longer period of time. Further, there just is not the same level of field operations, pro-Clinton early voting, or game changing media event in play. My gut feeling is that Obama wins Wisconsin by about 5-6%, although a victory in the low double-digits is not impossible. |