Previous studies of the U.S. Constitutional Convention have relied on votes recorded for the state blocs or a relatively small number of delegate votes. We construct a new data set covering delegate votes on over 600 substantive roll calls, and use the data in several ways. First, we estimate a single dimensional position for the delegates which reflects their overall voting patterns. Next, we explain these positions using a variety of delegate and constituent variables. Finally, we suggest a method for identifying state and floor medians, which can be used to predict equilibrium outcomes at the Convention.