The Discerning Texan
-- Edmund Burke
Wednesday, July 25, 2007
How the Washington Post (and others) jury rig their Polling
After a few years of relative equality, Democrats have pulled ahead of Republicans in party affiliation, as NBC noted in February. Nationally, Democrats enjoy a 34.3%-30.4% advantage in registrants. This has caused some analysts to predict that the GOP will have a tougher time in the Electoral College than in the last two elections, which was the general point of the article.
Now let's look at the Washington Post sample. On question 901, respondents answered that they were 35% Democrats, which is close enough to the national average. However, only 23% identified themselves as Republicans, which amounts to a 24% underrepresentation (see update below) of the GOP in this sample. In fact, the Post consistently underrepresents Republicans, and has for the past two years. The last time it came close to reality was in November 2006 -- when the Post needed to make sure its election predictions came close to the results.
Not surprisingly, that was also the last time the Post's polling on George Bush's approval ratings came close to reality, too. His disapproval then was 57%, which the elections seem to have confirmed. At the time, Rasmussen -- which has been historically more accurate than the Post -- had it at 56%. They now have it at 59%, actually down from a high of 65% in the first part of July during the immigration debate.
Bush is not popular, by any means. However, by seriously underrepresenting Republicans in its polling samples, the Post exaggerates his unpopularity and renders its polling unreliable. If their pollsters cannot generate a sample that resembles the American electorate, then they should find new pollsters.