John Bullock
2020 February 27

In Partisan Bias in Factual Beliefs about Politics, my co-authors and I examined factual matters about which Democrats and Republicans seem to hold different beliefs. Many of the matters that we examined were about the economy or war: for example, Democrats and Republicans seem to differ systematically with respect to their beliefs about the unemployment rate and about the number of Americans who have been killed in Afghanistan. But we asked questions about other matters as well. And in our first experiment, fielded in 2008, we asked respondents to state their beliefs about John McCain’s age.

Several readers have objected to the McCain question. Their claim is that McCain’s age was not a salient political matter and that there is no reason to think that ordinary Democrats and Republicans were divided on this point.

There are two points to make in response. First, even if the critics were right, our analyses would not be much affected. Second, the critics are mistaken: McCain’s age was a salient point in the 2008 election.

Analyses Not Affected Much by Any Single Question

Consider the first point. The McCain question is just one of 21 questions that we analyze; our conclusions scarcely depend on it, or on data from any single question. In addition, if the criticism were correct—if partisans didn’t hold different beliefs about McCain’s age—the effect should be to weaken the effect of our treatment. To see this point, recall that, in our article, we examine whether payments for correct answers reduce the partisan gap between Democrats and Republicans. But if there is no partisan gap under ordinary circumstances, payments like ours can have no effect. The implication is that estimates of our treatment effect will be smaller.

McCain’s Age Was a Salient Issue in the 2008 Election

Now consider the second point: the claim that McCain’s age was not a salient issue in the 2008 election. This claim is simply a mistake. Note, to begin, that Democrats and Republicans did differ systematically in their beliefs about McCain’s age: see page 532 of our article. But the more general point is that, in the electorate at large, McCain’s age was a significant issue.

On the eve of the 2008 election, McCain was 72 years old. He was the oldest non-incumbent ever to win a major-party nomination. He had been a prisoner of war for six years, and he had been tortured repeatedly during that time; the torture left him with lifelong disabilities. He had also survived four bouts with melanoma. If he had been elected and re-elected—and if he had survived two terms of office—he would have been 80 years old by the time that he left the White House. And in 2008, Americans took note:

The weight of the evidence is clear: McCain’s age was a salient issue in the 2008 election.