Newcomer question

Somewhat new to bicycling and the racing.

I look at the standings posted by Bob Martin and from my viewing on
Versus. What sort of deficit is reasonable to make up at this point
based on historical efforts?

Frex, is Hincapie's almost .5 hour deficit something that has been
overcome by others in the past? At what point can we say that someone
with a deficit of X minutes is effectively out of the running for the
overall winner?