Given the openness of U.S. nominations, it may be easier for outsiders with no prior experience to use populist rhetoric to become a major party nominee than under systems with stronger party gatekeeping. As trust in Congress has decreased, experience narratives—where candidates advocate that they are best positioned to represent the party due to prior experience or reasons of competence—have declined in congressional primaries. Prior experience in office has historically been a strong predictor of success in elections, but its value has lessened in the past decade. At the same time, the use of populist rhetoric—positioned here as the preferable definition of populism—has risen in primary campaigns. I find that prior elected legislative experience became less frequent among major party candidates using an original dataset of U.S. House of Representatives primaries between 2006 and 2018. This chapter considers competing definitions of populism, before examining the specificities of populist rhetoric in the U.S., I demonstrate that as populist rhetoric has become more prevalent, where a decline in nomination contests focused on prior experience has coincided with a reduction in ‘quality’ among non-incumbent candidates.