Biden's lead shrinking in latest CBS News Battleground Tracker poll
CBS News' latest Battleground Tracker poll shows former Vice President Joe Biden's lead shrinking, as Senators Elizabeth Warren and Kamala Harris gain ground. CBS News Elections & Surveys Director Anthony Salvanto, CBS News political correspondent Ed O'Keefe, and Edward-Isaac Dovere of The Atlantic spoke to CBSN's "Red & Blue" about the state of the race.