Robert Kennedy Jr. is set to announce his running mate this week. To mark the occasion, Semafor’s Dave Weigel explains whether third-party options can move the needle. This episode was produced by Miles Bryan, edited by Amina Al-Sadi, fact-checked by Anouk Dussaud and Laura Bullard, engineered by Patrick Boyd, and hosted by Sean Rameswaram. Transcript at vox.com/todayexplained Support Today, Explained by making a financial contribution to Vox! bit.ly/givepodcasts Learn more about your ad choices. Visit podcastchoices.com/adchoices