The Trump administration proposed changing the 2030 census so that only U.S. citizens and lawful permanent residents would count toward population totals. The Census Bureau submitted the proposal Wednesday after President Trump directed the Commerce Department to prepare a census that excludes immigrants living in the country illegally.

The plan would go further by excluding people on temporary visas and removing questions about race and ethnicity. The public has 30 days to comment before the administration moves forward. Census totals have major repercussions for congressional seats, which will influence federal funding and projects for states and communities.

The proposal will almost certainly face legal challenges. The 14th Amendment requires House seats to be apportioned using the whole number of persons in each state. During President Trump’s first term, the Supreme Court blocked his administration from adding a citizenship question to the 2020 census after finding that its stated justification was contrived.

Census results determine how the 435 House seats are divided among the states and influence everything from funding for roads, schools, hospitals, and emergency services. Excluding temporary and illegal immigrants would likely have pronounced consequences for states like California, Texas, Florida, and New York, where both legal and illegal immigrant populations are substantial. If large swaths of people are left off the census in these states, political power could shift in a very notable way.

The administration believes that representation should reflect citizens and permanent members of the country rather than everyone physically present, while opponents point to the Constitution’s instruction to count the ‘whole number of persons’ in each state, likely returning the issue to federal court.

While the new count would not occur until 2030, the proposal gives Republicans a clear immigration and representation issue ahead of the midterms, while Democrats are likely to argue that the change would undercount communities and distort government planning. The eventual outcome would strongly influence congressional control for at least a decade, as census figures shape district maps and House apportionment until the next national count.

Voting for citizens and permanent residents would not change much, but drastic drops in population numbers would still change things to varying degrees. Public agencies would still serve residents excluded from the census, but they could receive funding based on a population smaller than the one they actually support.

Population figures help determine where governments build infrastructure, and to a large degree, how much and how large. Under the proposal, census totals would exclude people who still use these systems, so communities may appear smaller than they are.

Ballots may also change over time as well, since new population totals may redraw congressional boundaries and your home may be rezoned into a different district. On a larger scale, this could also noticeably affect the influence individual states have on presidential elections.