Just How Wrong are the NC Polls?

Looking back at my previous post There is no Bradley Effect!, I couldn’t help but notice a pronounced pattern: The four states in which Obama outperformed the polls by at least 10% were all states with relatively high African-American populations. Intrigued, I decided to see if this pattern would hold for other high-AA states (including DC). Since RealClearPolitics didn’t have published polling data for a number of these states, I turned to usaelectionpolls.com to fill in the gaps. Here is what I found:

State	% AA	Actual Spread	Poll Spread	Difference
DC	57	51.5	36	15.5
MS	36	24.5	15.4	9.1
LA	32	21.8	*	*
SC	28	28.9	11.6	17.3
GA	27	35.3	18	17.3
MD	27	24.9	22.3	2.6
AL	25	14.4	-1.2	15.6
NC	20		8.2
DE	19	10.8	-2	12.8
VA	18	28.2	17.7	10.5

*No polling data was available for Louisiana.

The pattern is remarkable. There seems to be a consistently high error rate in these states, with Obama outperforming the polls by an average of 12.6%. One must conclude that there is some systemic bias in the pollsters’ methods that underestimates the level of AA support for Obama. My guess is that the models used to determine Likely Voters fail to account for unexpectedly high turnout among the AA population.

There is one anomaly in the data: Somehow, the polls predicted Maryland with reasonable accuracy. I have no explanation for why that sole state managed to buck the pattern.

But now comes the fun part – predictions! The current RCP average for NC gives Obama an 8.2% edge over Clinton. But if he outperforms the polls by the expected 12.6%, then his win will actually be 20.8%. You heard it here first!

At least one pundit has opined that Clinton has an outside chance of winning NC. Based on the analysis here, I would advise Clinton supporters to avoid setting expectations for even a single digit loss.

Update (5/5/08): As of the eve of the primary, Obama's edge for NC has gone down to 7.0%, according to RCP. That brings my prediction down to 19.6%, plus or minus the usual margin of error. Let's see what happens!

It's the Charisma, Stupid!

At this time of the quadrennial presidential cycle, it's common to start handicapping the prospective nominees' chances against each other. But polls taken this far ahead of the general election are notoriously terrible at making any kind of accurate prediction. So what factors have proven to be reliable predictors in the recent past?

Not intelligence. Unless you care to make the claim that GWB was as intelligent as either of his two opponents.

Not experience. Clinton and GWB both won their first terms against more experienced candidates.

Not the economy. Otherwise, Al Gore would have won in a landslide.

But there is one factor that has been a consistently accurate predictor in every election since television became important in presidential politics - charisma. Since Kennedy vs. Nixon, every election that featured a significant charisma gap between the two candidates ended up in favor of the more charismatic of the two. This includes six of the last seven elections, including both Reagan terms, both Clinton terms, and both GWB terms. Reagan and Clinton were both exceptionally gifted in terms of charisma, whereas GWB was gifted with especially uncharismatic opponents.

When was the last time that a presidential candidate with clearly superior charisma lost in the general election? I believe that would be 1956, when Adlai Stevenson lost to Eisenhower. Not coincidentally, the first televised presidential debate was in the 1960 election. Since then, the only elections that have not been predictable based on charisma have been those without a significant charisma gap, such as George HW Bush vs. Michael Dukakis.

Charisma is not as useful a predictor in primaries. After all, Ford did beat Reagan in the fight for the 1976 nomination. Apparently primary voters are more frequently motivated by other factors than general election voters. This, of course, is why the parties often do a poor job of nominating an electible candidate, and also why Huckabee is not the presumptive nominee for the GOP.

Why is it that charisma is so powerful as a predictor of presidential elections? I believe there are three main reasons:

• Direct persuasion. This is the obvious one. Voters like to vote for the more likeable candidate. This seems to be especially true among those all-important swing voters who remain undecided until the last minute. Those voters are the ones without strong policy convictions; otherwise they would have made up their minds sooner. So they are more prone to vote based on personality. I have distinct memories of the Bush vs. Gore campaign, when swing voters would tell interviewers things like, "I just couldn't take the idea of hearing Gore's voice on the TV news every night for the next four years."
• Vulnerability to mudslinging. Is it any coincidence that Reagan the Great Communicator was also known as the Teflon President? That he could dissolve concerns about his age with a single well-delivered one-liner in a debate? Clinton survived impeachment, whereas John Kerry couldn't fend off the Swift Boat attacks. The fact is, mud doesn't seem to stick well to charismatic candidates. People want to like likeable people.
• Enthusiasm. A charismatic candidate is better able to inspire hordes of dreamy-eyed twenty-somethings to knock on thousands of doors, or to volunteer to ferry senior citizens to and from voting locations on election day.

Regardless of the cause, this reasoning indicates that McCain is in for a tough fight should Obama become the Democratic nominee. The charisma gap between the two men is as large as Reagan-Mondale, and could easily lead to a blowout as big.

Interestingly enough, the most charismatic candidate from this year's GOP field - Mike Huckabee - seems to be setting himself up for a possible 2012 run. Should that happen after an Obama victory in 2008, then we might see the first modern campaign that featured two highly charismatic opponents.

Now that would be interesting.

There is no Bradley Effect!

After Hillary Clinton's surprise win in the New Hampshire primary, speculation abounded that Obama was the victim of the so-called "Bradley Effect". After her win in California, such speculation resurfaced. The theory is that closet racists would lie to pollsters about their willingness to vote for a black candidate. This would cause the black candidate's vote tally to lag behind the polls' predictions.

But is this really true? critics of the Bradley Effect hypothesis have pointed to other possible explanations for New Hampshire and California, such as Clinton's display of emotion before the NH voting, and California's early voting.

To put the argument on a solid footing, I reviewed the results of all the primaries to date, to see if there was any evidence of a systemic Bradley Effect. Here was my methodology:

First, I identified states that met these three criteria:

• Used primaries instead of caucuses. This is because proponents of the Bradley Effect explanation have claimed that the Bradley Effect is only evident in the privacy of the voting booth. Supposedly the public nature of the caucus is enough to keep closet racists in the closet.
• Had polling data available from the week before the primary date. Any discrepancy between older polls and the election results are too easily explained by late surges.
• Have already held their primaries. For obvious reasons.

As of today (Februrary 14), seventeen states meet these criteria. For each of these states, I compared the vote spread between the two candidates to the average poll spread as reported by RealClearPolitics.com. (For some reason, RCP didn't average the poll spreads for Oklahoma, so I just took the average of the spreads from the last four polls.) I then sorted the results by the difference between the actual spread and the RCP spread. Here are the results:

State	Actual Spread	RCP Spread	Difference
GA	35.3% Obama	18.0% Obama	17.3% Obama
SC	28.9% Obama	11.6% Obama	17.3% Obama
AL	14.1% Obama	1.2% Clinton	15.3% Obama
VA	28.2% Obama	17.7% Obama	10.5% Obama
CT	3.1% Obama	4.0% Clinton	7.1% Obama
MO	1.2% Obama	5.7% Clinton	6.9% Obama
FL	16.7% Clinton	19.6% Clinton	2.9% Obama
OK	23.6% Clinton	25.5% Clinton	1.9% Obama
MD	23.5% Obama	22.3% Obama	1.2% Obama
NY	17.5% Clinton	17.2% Clinton	0.3% Clinton
TN	13.3% Clinton	13.0% Clinton	0.3% Clinton
IL	31.5% Obama	33.0% Obama	1.5% Clinton
NJ	9.8% Clinton	7.7% Clinton	2.1% Clinton
AZ	8.8% Clinton	6.0% Clinton	2.8% Clinton
MA	15.0% Clinton	7.0% Clinton	8.0% Clinton
CA	9.6% Clinton	1.2% Obama	10.8% Clinton
NH	2.6% Clinton	8.3% Obama	10.9% Clinton

These results yield some interesting observations:

• Obama beat the polls' expectations in nine races, whereas Clinton beat the expectations in eight.
• In six races, Obama beat the expectations by more than the 3-4% margin of error. Clinton only did so in three races.
• The two supposed Bradley Effect races were the only two in which Clinton beat expectations by more than 10%. Obama accomplished this in four races.

If the Bradley Effect were real, we would expect to see a trend of Clinton outperforming expectations. In fact, we see no such trend, and perhaps even a small trend in the opposite direction.

This is not to say that racism is not playing a role in the primaries. Remember that the Bradley Effect is a particular kind of racism - one in which voters lie to pollsters, distorting the poll results. Racists who are honest about their candidate preference are a different matter entirely.

Rather than focusing on the non-existant Bradley Effect, perhaps we should instead be questioning the dismal track record of the horserace polls this season. With over half of the spreads outside of the polls' statistical margin of error, there would appear to be some significant problems with the pollsters' methodology.