However, things changed in 2015 when Donald Trump announced his bid for the presidency. Since then opposition rose upwards among the general public. Analyzing more than 150 polls conducted between 2007 and 2018 from the Roper Center iPoll Databank reveals that an average of 43 percent of Americans opposed building a border wall between 2007-2014. Opposition increased to 48 percent in 2015, 58 percent in 2016, and 61 percent in 2017, and then back to 59 percent in 2018.

Democratic support shifted more swiftly starting in the fall of 2015 onward. Now only about 12 percent of Democrats support a border wall or fence. As the charts above demonstrate, Trump’s entry into politics (and making immigration issues salient) played a major role in turning the public against the border wall.