According to an AP wire story,
The 2008 Republican platform...says only those legally residing in the United States should be counted in the next census.
"The integrity of the 2010 census, proportioning congressional representation among the states, must be preserved," says the platform language, which is a reinterpretation of the Constitution that could affect how congressional seats are apportioned. "The census," it says, "should count every person legally abiding in the United States in an actual enumeration."
The 14th Amendment of the Constitution, ratified in 1868, says that representatives to the U.S. House "should be apportioned among the several states according to their respective numbers, counting the whole number of persons in each state, excluding Indians not taxed."
"Our mandate is to count all residents regardless of legal status," said Mark Tolbert, a spokesman for the Census Bureau.
Interesting, if unfortunate. Will a McCain Presidency actually alter the 2010 census, or is the platform just rhetoric to be ignored if the candidate is actually elected? as far as I know, the Democrats have made no suc statement in their platform.