Erik, he wants to see if the pin is LOW (which would indicate to him if it is floating), so I think what Michael said is correct

The only pins that can float are P0 ('normal' derivative) and such pins will be low if no input is provided (floating). P1, 2 and 3 all have weak internal pullups and will be high if nothing is connected to the pin (again 'floating').

There must be something here I do not understand since the above show that no resistor is needed unless you want P0 and the other ports reading the same way.

Erik