[MrLeRoy]

The Census requires all "persons" to be counted

Wrong---it requires all "free persons" to be counted.

[Mark Bahner]

"Wrong---it requires all "free persons" to be counted."

No, you're looking at an obsolete version. See Amendment 14:

"Section 2. Representatives shall be apportioned among the several states according to their respective numbers, counting the whole number of persons in each state, excluding Indians not taxed."

Since the unborn have never been counted to apportion Representatives to the U.S. House of Representatives, the unborn must not be persons.