Some really great analysis on why Mitt wins Ohio!
by Trevor Antley and
Calvin Roberts.
Forecast: Mitt Romney Will Likely Win Ohio
Abstract:
Actual reported early voting data requires that early voting will represent no
more than 32% of total vote in Ohio, while virtually every poll was weighted
for early voting to occupy ~35-40% of total votes cast. The
smaller-than-expected number of early votes means one of two things: 1) 2012
will see historically low voter turnout in Ohio; or 2) Mitt Romney has a much better
chance at Ohio than polls assumed.
Late Monday night the
Ohio Secretary of State released the “final” early voting results from Ohio’s
counties. The results got the attention — and slight consternation — of the New
York Times’ Nate Silver. Dave Wasserman kindly put the data
into a spreadsheet here, which tabulates early voting results by county and
compares that data to early voting results from 2008. Wasserman’s spreadsheet
also notes Kerry’s 2004 margins and Obama’s 2008 margins, allowing one to
effectively deduce the partisan-leanings of each county.
In a discussion on
Twitter, Silver and Wasserman focused largely on the surprise changes in
turnout in many of Ohio’s counties. While total early voting in Ohio only
increased by 2.44% from 2008, early voting in counties that voted heavily for
Kerry/Obama declined 4.1% while counties that voted heavily Bush/McCain
increased their early voting by a shocking 14.39%. Wasserman, while still
predicting an Obama victory, suggested that trend meant a tighter race in Ohio
than expected and suggested it might undercut Nate Silver’s famous forecast. Nate Silver’s response: “I’ll stick with the 538 forecast in
OH. I disagree that the early voting data there provides much reason to doubt
the polls.”
Seemingly overlooked
by Silver, however, during the discussion of county-by-county results was the
simple number of total reported early votes: a meager 1,787,346. As stated
above, this number shows a 2.44% increase in early voting from 2008 — but the
number is still surprisingly low. Virtually every Ohio poll this cycle was
weighted on the basis that early voting would occupy a massive chunk of the
total Ohio vote. Rasmussen’s final poll ceded 40% of the total vote to early
voters (EVs). PPP gave EV’s a more reasonable 35%. The Columbus Dispatch
calculated early voting to take up an astounding 47% of the total Ohio vote.
Almost every other Ohio poll seems to have weighted early voting between 35%
and 45% of the total vote.
The reported early
voting numbers, however, show that virtually every single Ohio poll
overestimated the amount of early votes cast. If early voting is calculated at
1,787,346, in order for total voter turnout to rival 2004 numbers, early voting
cannot occupy more than 32% of the total votes cast — and even in that
scenario, that high of a percentage means that total voter turnout will be
lower than it was in 2008. In order for turnout to match 2008 levels, early
voting can only account for 31% of total votes cast.
The next important
piece of data is what the polls consistently report: Obama leads by huge
margins among early voters but trails Romney among those who say they will vote
on election day. This inverse in voting segments is why the proportion of early
votes in the total votes — and that virtually every poll overestimated this
proportion — is so tantamount. In most polls (which usually only have Obama
leading by a small margin, although some give him a more comfortable ~+5%),
lowering the percentage of early votes in the polling sample means lowering
Obama’s lead drastically. And when Obama’s lead is only one or two percentage
points, that can mean handing the election to Mitt Romney.
Our forecast is based
largely on the reported margins between Romney and Obama among early voters and
election day voters as reported by the Columbus Dispatch, Rasmussen, and other
polls (all polling data considered is represented in the graphic below). The
Columbus Dispatch gives Obama +15% among early voters; Rasmussen gives him a
much wider 23%. Other polls for Ohio EVs: CNN/Opinion Research, Obama +28;
Gravis Marketing, Obama +13; PPP, Obama +21. For our forecast we assumed a more
conservative Obama +18 among EVs, averaging Rasmussen and the Columbus
Dispatch.
In 2008 Obama won 58%
of early voting against John McCain, who had virtually no get-out-the-vote
infrastructure in Ohio; our model, giving Obama a 18% lead, again assumes he
will win that 58% of early voters despite the fact that Mitt Romney is putting
forth a much more competitive get-out-the-vote campaign and disregarding the
GOP-leaning trend in early voting results of individual Ohio counties. When one
considers the results from individual Ohio counties this cycle, Obama’s actual
margin among EVs may actually be much lower (although without specific partisan
data, it’s also possible that Obama’s margins have actually increased —
although this seems extraordinarily more unlikely). But because this is
impossible to determine without actual breakdowns of the early vote, which are
not yet available, those implications are not included in this model.
In determining the
margin among election day voters, the same polls were considered. For election day voters,
Rasmussen has Romney +15; Columbus Dispatch, Romney +11; and CNN/Opinion
Research, Romney +13. PPP and Gravis Marketing both had Romney’s election day
margins at a much smaller +3. For our forecast, we assume Romney’s election day
voter margins at 13%, an average of the first three polls. The consistency and
disparity between the first three and the latter two polls made it difficult to
average them since margins of error do not explain such a
clear discrepancy between the two groups.
In this scenario —
which seems to be supported by the majority of polls and early voting trends
(but is notably not supported by all polls, as seen in the previous paragraph) — Romney should win
Ohio. Based on these assumptions — which in turn are based on a combination of
polling data and the state’s actual reported early vote — if early voting
accounts for 32% of the vote (a very conservative number which would place
total voter turnout slightly below that of 2004), Romney wins by a whopping
50.9% to Obama’s 47.8%. The higher voter turnout is — and therefore the lower
the percentage of early votes in total votes — the higher Romney’s margin
becomes.
In this scenario, even
if we assume our model’s margins between Obama and Romney among early voters
and election day voters are somehow skewed in Romney’s favor, Romney still has
padding that those margins could be reduced and he still wins. If early voting
is only 31% of the total vote — putting Ohio’s total vote at just above 2008
levels — Romney has incredibly more wiggle room.
http://josephantley.files.wordpress.com/2012/11/ohioresults.png
The
lower-than-anticipated turnout among early voters suggests the Obama campaign’s
lead in Ohio was largely hot air. And this does not even seriously consider the
county-by-county early voting results, which appear to be even more damaging to
Obama.
Reasons Why This Projection May Turn Out to be Wrong
·
In the case that the
final early voting numbers reported by the Ohio secretary of state are
incorrect and the final early voting results will include statistically
significant additions, obviously this projection will have no meaning.
·
As seen above, some of
the polling data used in the projection (such as Romney’s margin among election
day voters) is supported by several independent polling organizations but not
by some others. If it turns out that the fewer polls’ results were right, then
obviously our entire model is skewed too heavily towards Romney.
·
Some have raised the
possibility that effects from Hurricane Sandy stifled early voting in the final
days and these early voters will simply vote for Obama on election day,
increasing his election day margins beyond what polls indicated. In this
scenario the polls are essentially still correct; Obama’s early voting margin
was simply reallocated to his election day margin. There is no solid data to
show that this is the case, but it is certainly possible.
·
There is always the
chance that the government and electorate will decide simply to defer to Nate
Silver’s forecast and forget this whole voting nonsense. Since our forecast is
based largely on actual votes, not subjectively weighted aggregates of polls, this would make
our projection essentially meaningless.
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