Biden's frontrunner status comes with Burisma baggage: Yahoo News Explains

Joe Biden's resurgence as a frontrunner in the Democratic presidential primary has reopened the door for attacks on his record as vice president. While Bernie Sanders enjoyed the lead, Republican attacks focused on the need to defeat "socialism," but they are now shifting to Biden and his son Hunter's connections to the Ukrainian energy company Burisma. Yahoo News Senior Political Correspondent Jon Ward explains how Republicans may use ongoing investigations into Burisma as political leverage in the general election.