At the Iowa Republican caucuses on Monday night, Donald J. Trump secured a runaway victory. The only real drama was the fight for second place.\n\nReid Epstein, who covers politics for The Times, takes us inside one of the caucuses, and Shane Goldmacher, a national political reporter, walks us through the final results.\n\nGuest: Reid J. Epstein, a politics correspondent for The New York Times, and\n\nShane Goldmacher, a national political reporter for The New York Times.