In three studies conducted over the course of 2016 US presidential campaign we examined the relationship between radicalism of a political candidate and willingness to engage in actions for that candidate. Drawing on significance quest theory (Kruglanski et al., 2018), we predicted that people would be more willing to make large sacrifices for radical (vs. moderate) candidates because the cause of radical candidates would be more personally important and engagement on behalf it would be more psychologically rewarding. We tested these predictions among supporters of Hillary Clinton, Donald Trump, and Bernie Sanders. Our findings were in line with these predictions, as the more followers perceived their candidates as radical, the more they viewed leaders’ ideas as personally important, gained more personal significance from those ideas, and intended to sacrifice more for the leader.