A judge ruled this week that Robert F. Kennedy Junior’s name will remain on the Michigan ballot as the presidential candidate for the Natural Law Party. Will RFK Jr., Jill Stein and Cornel West be 2024’s election spoilers? Zoe Clark and Rick Pluta speak with Brooking Institution’s Elaine Kamarck, author of “Primary Politics: Everything You Need to Know About How America Nominates Its Presidential Candidates” about the role of third parties this election cycle.