The only fair way to get representation in the House is by making sure citizens are counted separately

Bryan Preston:

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Both the original language in Article 1, Section 2 and the 14th Amendment tie the census directly to representation in the U.S. House of Representatives. This is important to understanding the purpose of asking about citizenship on the census.

Inquiring about citizenship on the census goes back to at least 1800 and Thomas Jefferson. The founder, author of the Declaration of Independence and president-to-be wanted the census to ask about the “respective numbers of native citizens, citizens of foreign birth, and of aliens...for the purpose of more exactly distinguishing the increase of population by birth and immigration.” In 1820 the census began asking the questions President Jefferson wanted answered.

Citizenship was deeply important to the founders. Their revolution was about replacing the concept of the subject of the crown with that of the self-ruling citizen. As John S. Baker of Our Citizenship Counts recently wrote in The Hill:

The United States was the first nation since the ancient Greek and Roman republics to establish citizenship. American colonists were “subjects” of the British Crown. Even in the ancient republics and pre-Civil War United States, citizenship was limited. Other inhabitants — whether slave or free — did not participate in governing.

Citizenship has been routinely asked in the census in one way or another. Up to the 1950 census, citizenship was asked either directly or as a follow up of all respondents. Citizenship was removed from the short questionnaire in 1960 but was included on the longer questionnaire that went to a subset of census respondents starting in 1970 – until 2010. President Obama dropped the long form altogether in 2010, thereby dropping the citizenship question.
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But the real purpose of failing to ask about citizenship may be to undercount and under-represent citizens and give states that attract more non-citizens more House representation than they are due. Failing to ask about citizenship may also make enforcement of voter fraud more difficult, by making counts less accurate.
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California’s high illegal immigrant population translates directly into three House seats. California can negate smaller states' House representation by granting more largess to non-citizens. Other blue states can follow California’s lead, growing their own House representation through attracting illegal immigration and squeezing swing states like Ohio and Pennsylvania, which tend to be in the middle range of House seat allocations.
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Those stolen seats in the Hosue also translate into stolen electoral votes which also robs other states of influence in the Presidential election.  Without the Census question, illegal sanctuary states get underserved Hosue seats and electoral votes.