But that doesn’t keep him in the race, there are moron candidates with moron voters in other countries but they generally drop out pretty quickly. What keeps Trump in the race is mostly the electoral college but also the first past the post voting. Trump wouldn’t have a shot at winning if the electoral college didn’t skew the value of individual votes and first past the post effectively limits the amount of candidates you can have.
He’s not talking about the communist manifesto, he’s talking about Das Kapital. If you don’t care to read it there are YouTube summaries such as this one . If you want to get straight into the meat of the subject you can start from chapter 4 and if you think it’s all stupid take the 5-6 minutes to listen to chapter 7 so you’d at least know where socialists are coming from when they say capitalists are stealing your money.