A new CBS News Battleground Tracker poll shows a tight race in Iowa, with Joe Biden, Bernie Sanders, Pete Buttigieg and Elizabeth Warren all within the margin of error of each other. Antjuan Seawright, a CBSN political contributor and Democratic strategist; Eugene Scott, a political reporter for the Washington Post; and Larry Sabato, director of the University of Virginia's Center for Politics, spoke to CBSN's Tanya Rivero about the state of the 2020 presidential race.
