|99.3% probability of winning||0.7% probability of winning|
|Mean of 323 electoral votes||Mean of 215 electoral votes|
Nine new state head-to-head polls have been released in the contest between Presidential hopeful Mitt Romney and President Barack Obama since my previous analysis:
The unsurprising polls include one from Oregon that gives Obama a +8% lead over Romney, and the first poll of the year in Utah that gives Romney a +42% advantage over Obama.
The fourth Michigan poll released in the past week has the race tied at 40% each. Combined with two other recent polls, Obama has the slightest lead in the state overall, giving him an expected 68% probability of taking the state (if the election was held now).
The second New Hampshire poll in a week has Obama up by a tight +3% over Romney. (Note that I used the Likely Voter results instead of the Registered Voter results given for this poll.) The pair of polls combined gives Obama an 81% chance of taking the state at this point.
Two new Virginia polls split. One goes to Obama by +7% and the other goes to Romney by +4.7%. The weight of the evidence from the five recent polls is that Obama would take the state now with a 83% probability.
I want to again express my gratitude to Sam Minter, who does his own poll aggregation exercise. Sam systematically compared our poll databases, resolved the discrepancies, and sent corrections to me over the past month. Also, I thank the HA commenter who noticed an error in the Nebraska past elections numbers, and persisted in getting through to me when I missed his comment.
Okay…so now, after 100,000 simulated elections, Obama wins 99,310 times and Romney wins 690 times (including the 63 ties). Obama takes (on average) 323 to Romney’s 215 electoral votes. For an election held now, Obama would have a 99.3% probability of winning and Romney, a 0.7% probability of winning.
Since the previous analysis Romney has gained an expected +3 electoral votes and has more than doubled his probability of winning (now), but that works out to less than a 1% probability overall of winning.
Here is the distribution of electoral votes [FAQ] from the simulations:
Ten most probable electoral vote outcomes for Obama:
- 318 electoral votes with a 2.50% probability
- 323 electoral votes with a 2.49% probability
- 317 electoral votes with a 2.35% probability
- 328 electoral votes with a 2.29% probability
- 324 electoral votes with a 2.19% probability
- 319 electoral votes with a 2.12% probability
- 329 electoral votes with a 2.11% probability
- 335 electoral votes with a 2.05% probability
- 334 electoral votes with a 2.03% probability
- 327 electoral votes with a 1.94% probability
After 100,000 simulations:
- Obama wins 99.3%, Romney wins 0.7%.
- Average (SE) EC votes for Obama: 323.0 (20.8)
- Average (SE) EC votes for Romney: 215.0 (20.8)
- Median (95% CI) EC votes for Obama: 324 (280, 361)
- Median (95% CI) EC votes for Romney: 214 (177, 258)
Each column of this table shows the electoral vote total aggregated by different criteria for the probability of winning a state (Safe=100%, Strong=90%+, Leans=60%+, Weak=50%+):
|Threshold||Safe||+ Strong||+ Leans||+ Weak|
This table summarizes results by state. Click on the poll count to see the individual polls included for the state.
|8||4||Votes||polls||Votes||Obama||Romney||% wins||% wins|
* An older poll was used (i.e. no recent polls exist).
Details of the methods are given in the FAQ.
The most recent analysis in this match-up can be found from this page.