The 2016 Republican presidential nomination challenges arguments about political party insiders’ influence on the outcome. This article argues, first, that party insider influence is conditional on the participation, coalescence, and timing of party stakeholders behind a front-runner during the invisible primary, and second, that party insider influence has probably declined since the 2000 presidential election. Data on endorsements by elite elected officials in open presidential nominations from 1984 to 2016 show that party insiders’ participation and convergence of support behind the front-runner is less extensive than what was found by Cohen, Karol, Noel, and Zaller (2008), though the data sets differ. Party insiders participate and unify more readily when the party coalition is stable and there is a candidate in the race who has demonstrable national support. Party elites remain on the sidelines when the party coalition is divided or when there is uncertainty about the appeal of candidates (Ryan 2011; Whitby 2014). The potency of insider endorsements likely has declined with the rise of social media, the changing campaign finance landscape, and the reemergence of populism in each party.