Joe Biden Surges After 'Big Tuesday' Primaries, Sanders Says He's Staying In The Race

Joe Biden won four of six states that went to the polls Tuesday, securing his lead for the Democratic nomination. Biden won every county in Michigan, a blow to Bernie Sanders, who staked much of his campaign on the state.

Plus, the national spread of coronavirus has begun to affect the presidential race.

NPR's Scott Detrow (@scottdetrow) talks to host Jeremy Hobson about Tuesday night's results.