You’ve conducted extensive research on Oprah’s role in the 2008 presidential election. Did she actually influence voters?

Along with Timothy J. Moore of the University of Maryland, I analyzed the effect of Oprah Winfrey’s endorsement of President Obama during the 2008 Democratic Presidential primary. By examining county level differences in the circulation of her magazine along with difference in vote totals, we found that she was responsible for approximately one million extra votes for the President. While there are many other factors that decide the winner of an election, this amount was greater than the difference in total votes between the President and then-Senator Clinton in our sample of states.

If she had backed Hillary, would it have made a difference in the outcome?

It is really hard to say what the impact would have been. Looking at the majority of her viewers, we would generally expect that they are, on many dimensions, more like the average Clinton voter than the average Obama voter. Therefore, if many of her followers were already going to vote for Senator Clinton, her endorsement may have had less of a causal effect. It would be hard to attribute votes to Oprah’s influence if those voters were going to choose that candidate anyway.