https://www.politico.com/f/?id=0000016a-a480-dbd0-ad7e-e6ef4b840001
Biden 39%
Sanders 16%
Warren 5%
Harris 5%
Buttigieg 3%
O'Rourke 1%
Booker 1%
Klobuchar 1%
Only includes about 36% voters age 54 and under, but it's Florida, the state with the largest population of older folks.
Florida's primary is 3/17/2020, 2 weeks after Super Tuesday and it has 219 Pledged Delegates.
https://www.politico.com/story/2019/05/11/joe-biden-florida-1317604