Over the past few months, many journalists and pundits have credited the power of Donald Trump’s endorsements with determining the winners of Republican primaries. Trump has made 203 candidate endorsements in the 2022 election cycle so far, targeting state, congressional, gubernatorial and even local races. Based on the numbers alone, receiving a “Trump bump” seems like a surefire way to win an election. So far, 94% of Trump’s favored candidates have won their Republican primaries. But as a political scientist who studies voting and public opinion, I have my doubts about the true power of Trump’s endorsements. Instead, it is...