Trump attacks witnesses ahead of huge week of testimony; Aide who overheard Trump-Sondland call to testify Thursday; Swing state voters torn on who they will back in 2020; New poll: 0% of SC Dem black voters support Buttigieg

Eight witnesses expected to publicly testify this week; Amb. Sondland, who spoke to Trump about Ukraine, set to testify; House investigating whether Trump lied to Mueller; CNN goes to Kiev restaurant where Sondland called Trump; New CNN poll: Buttigieg leaps to first place in Iowa; New poll: 0% of SC Dem black voters support Buttigieg; White House stands by Stephen Miller after emails showed he pushed white nationalist conspiraciesTo learn more about how CNN protects listener privacy, visit cnn.com/privacy Learn more about your ad choices. Visit podcastchoices.com/adchoices