Exit Polls 2012, Ohio Exit Polling should give clues to the Romney v Obama 2012 Race

The US Presidential Election is here (as well as the US Senate, House, and thousands of local races) and we all would like to know the outcomes ... before the final tally.    Based on the best statistical analysis of polling through last week, Obama is the very likely winner of the presidential race.   Why?    Partly because Obama is winning in virtually all of the 'toss up" states where in some cases a small lead will translate into a very disproportionate number of votes.   Ohio, the key battleground, is leaning Obama and would give him 18 electoral votes. For Romney to pull off a victory he'll really need to "beat the odds" and win almost all the toss up states.    Obama, on the other hand, could lose more of the toss ups and still win the election.  

Based on Nate Silver's excellent statistical analysis from the New York Times, where he gives Obama a 91% chance of victory based on poll information, President Picker is predicting an Obama win today even before we see any exit poll information.    

What would have to happen for Romney to win?    Romney's hope is that the polls in battleground states have been biased in favor of Obama.   This seems unlikely but it is possible.   Conservatives may have been less likely to participate in the polls, methods may have included those who don't wind up voting, etc, etc.   However, contrary to many claims US polls, exit and otherwise, tend to be very accurate and a good predictor of election outcomes.   In 2000 for example, the exit polls stated that Gore won florida because ... he *would have won* Florida if the ballots in Palm Beach County had reflected voter intention.  These "butterfly ballots" led to confusion and many lost votes for Gore  (due to "overvoting" where people voted for both Gore and Buchanon for President and therefore the vote was NOT counted).    Exit polling was blamed in Florida when the real defect was the butterfly ballot of Palm Beach County   (designed and reviewed by Democrats, so unlikely to have been a conspiracy play to undercount Gore votes).

Today we'll be watching the toss up states - RealClearPolitics will have good coverage linked below.    Ohio is the key.   If Obama takes Ohio it's pretty much over.   However, if Romney takes Ohio it is likely to be a very long night, withe the prospect of another 2000 style election recount fiasco.

Toss Up (146)
CO (9)	FL (29)
IA (6)	MI (16)
NV (6)	NH (4)
NC (15)	OH (18)
PA (20)	VA (13)
WI (10)

Early voting polls

MSNBC is reporting a Diagio poll that shows Obama 48% and McCain 47% of early votes. This is more like an exit poll that a predictive poll and would appear to suggest a close race, though normally since early voting probably skews Republican this is not necessarily contradicting poll results.

Gallup on the other hand reports early voting polls are showing the same Obama lead that the normal polls show - a substantial margin and a huge positive sign for Obama.

http://www.gallup.com/poll/111430/Early-Voting-Now-11-Could-Reach-30.aspx

Missouri for Obama - unless you are AP

AP made a bad call on Missouri last night but otherwise the exit polling held up well. I was pissed in fact that they don't share this like they used to. When I saw the CA exit poll data from CNN, which very oddly leaves off the key total indicating the winner but include the female and male components and population percentages which should give you a good "exit poll winner" after a couple of math hoops and the assumption that males and females are voting in proportion to their state population.....hmm... but is this reasonable assumption?

I think folks make way too much of the challenges of exit polling. In general exit polling is good, but sometimes it is not. In 2000 the exit polling for Florida was fine - people *thought* they'd voted for Gore when in fact many ballots were spoiled due to double vote for Buchanon and Gore. This spoiled butterfly ballot factor clearly lost the race for Gore (crystal clear by the way if you missed the later analysis) even though it was not contested by him in the infamous Supreme Court decision which actually did not make a difference in the outcome.

So -Exit polls are good, but not always correct. Welcome to math.