In the wake of June’s Democratic presidential debate, most polling agrees that former Vice President Joe Biden is still the front-runner (although the size of his lead has taken a hit), followed by a rough three-way tie among Sens. Kamala Harris, Bernie Sanders and Elizabeth Warren. But as we already have seen numerous times this primary season, the standings are fluid. Many voters probably will change their minds between now and when voting begins. So it’s also valuable to take note of whom people’s second choices are. CONT.
Nathaniel Rakich, FiveThirtyEight