In 1998 Harry Pachon and Rudy de la Garza wrote a report for the Tomas Rivera Policy Institute titled "Why Pollsters Missed the Latino Vote - Again!"
in which they argued that polls across California failed to accurately
account for Latino voters in their samples, and that pre-election polls
statewide were fraught with errors as a result. Pachon and de la Garza
argued that "mainstream" pollsters failed to account for Latinos for
three primary reasons: 1) their sample sizes of Latinos were far too
small; 2) their Latinos samples were not representative of the Latino
population within the state; and 3) they were not interviewing Latinos
in Spanish at the correct proportions. THIS WAS 14 YEARS AGO (yes I am screaming).
now the worst offenders might be the newest batch of national polls are
attempting to estimate the national Obama-Romney horse race numbers.
Monday October 22, Monmouth University released a poll
in which Romney leads Obama 48% to 45%. Among Latinos, they report
Obama leads by just 6 points - 48% to 42%. These numbers are such
extreme outliers that even Romney campaign surrogates would have a hard
time believing them. While Monmouth is the most recent, there have been
many national polls with equally faulty numbers among Latinos.
that 48 to 42 number in your head and let's compare across a variety of
recent polls of Latino voters. As a matter of self-interest, we'll
start with four recent impreMedia-Latino Decisions tracking polls in
October. The last four polls released by IM/LD have found the Latino
vote nationally at 71-20; 67-23; 72-20; 73-21. Don't like those? NBC/Telemundo have released two polls in October of Latinos, putting the race at 70-25, and 70-20 just before that. And then there was the Pew Hispanic Center poll 10 days ago which had Obama 69-21 over Romney, and just before that CNN did a poll of Latinos putting the national vote at 70-25.
Okay - that's eight national polls of Latino voters in the month of
October and the average across all eight is 70.3% for Obama to 21.9% for
examine how these faulty Latino numbers create problems with the
overall national estimates. Afterall, Latinos are estimated to comprise
10% off all voters this year. If Latinos are only leaning to Obama
48-42, that +6 edge among 10% of the electorate only contributes a net
0.6 advantage to Obama (4.8 for Obama to 4.2 for Romney). However, if
instead Obama is leading 70.3 to 21.9 that +48.4 edge contributes a net
4.8 advantage to Obama (7.0 to 2.2), hence the national polls may be
missing as much as 4 full points in Obama's national numbers.
Let's break the numbers down a bit more to see if the math adds up, as Bill Clinton is so fond of saying...
at the Monmouth Poll, overall they give Romney a +3 edge nationally, 48
to 45. According to their crosstabs by race and ethnicity (posted here),
the first tab below shows the data as collected and reported by the
Monmouth Poll, including their estimates of the share each racial group
will comprise of the electorate. If you take the vote percentages for
each candidate times the share of the electorate that Monmouth gives
each group, you can arrive at the contribution that each racial group
makes towards the overall support numbers for each candidate.
the data as reported by Monmouth, Latinos would add 5.8 points to Obama
and 5.0 point to Romney, a net edge of 0.8 points towards Obama.
However, in tab 2, we plug in the 8-poll average among Latinos as
reported above, 70.3 to 21.9. Here, we see Latinos contribute 8.4
points to Obama and 2.6 to Romney, a net edge of 5.8 points towards
Obama. With this adjustment, that 5 point swing in the overall national
data towards Obama takes what was a +3 .6 advantage for Romney and
turns it into a +1.5 advantage for Obama, 47.6 to 46.1. This is the
exact story of the 2010 Nevada data in which poll after poll showed
Angle ahead of Reid, and Latinos only slightly breaking to Reid. On
Election Day Reid won by 5 points, an 8-point swing from the poll
average, and he carried Latinos 90-to-10.
we might also look at the Monmouth (or any of the national polls) data
among Blacks and expect they have underestimated the Black vote for
Obama. Rather than carrying 82% of the African American vote, a more
realistic prediction is that Obama will win 92% (or more) of the African
American vote. A recent NBC/Wall Street Journal poll showed 94% of Blacks
planning to vote for Obama and 0% for Romney. If we add 10 points to
the Black vote for Obama - an adjustment I doubt anyone would disagree
with - we find a full additional point in favor of Obama nationally,
48.7% to 46.1%.
of polls this year are making these exact same errors that Harry Pachon
and Rudy de la Garza pointed out 14 years ago. And by the way, their
report title carried the phrase "Again!" because they pointed out that
polls in California in 1994 and 1996 had made similar mistakes in
underestimating the Latino vote.
these mistakes are being made nationally where Latinos comprise an
estimated 10% of all voters, they are even worse in statewide polls in
Nevada, Florida, Colorado and Arizona where Latinos comprise an even
larger share of all voters. In Florida Latinos are estimated at 17% of
all voters. If you are badly mis-calculating the candidate preference
among 17% of the electorate (that's 1 out of every 6 voters), then the
entire statewide estimates are wrong. A PPP poll out yesterday
in Florida had Romney leading 49 to 46 among Latinos in Florida, and
overall Romney was ahead 48 to 47. The PPP poll likely had around 130
Hispanic respondents, all interviewed via robotic IVR method, which has
notoriously low and problematic response rates among Latinos. A Latino Decisions October poll showed Florida Latinos backing Obama 61 to 31.
and accurately polling the Latino electorate is important not just for
the sake of getting a correct portrait of Latino voters, but because
they are such a large part of the overall electorate that "missing the
Latino vote" ultimately results in missing the true vote of the entire
electorate, whether in a swing state, or nationally.