One way that Donald Trump launched onto the political stage five years ago was through his fervent claims that President Barack Obama was not a U.S. citizen. Though Obama has since produced birth certificates certifying his birth in Hawaii, recently, such rumors have been given new life by commentators and pundits on the right. But just how many continue to think the president was not born in the U.S.? And which voters hold such views?

Seventy-two percent of registered Republican voters still doubt President Obama’s citizenship, according to a recent NBC News|SurveyMonkey poll conducted in late June and early July of more than 1,700 registered voters. And this skepticism even exists among Republicans high in political knowledge.

To see whether voters believe that Obama was not born in the United States, we asked them about their agreement with this statement: “Barack Obama was born in the United States.” The chart below shows responses broken down by party identification.