Here are some numbers to mull over: 6,000, 15,000, and 14,000.  That's roughly the number of delegates, media members, and hotel rooms booked at the last Democratic National Convention in Charlotte, North Carolina in 2012.

The convention is a big event with a big potential upside for the host city.  And next year, that host city will be Philadelphia.  WHYY's Senior Reporter Dave Davies talked with convention CEO Leah Daughtry to find out what it takes to pull it all off.