The Trump administration is seeking to change how the 2030 census determines each state’s share of power in Congress and the Electoral College, proposing to exclude residents who are not U.S. citizens or green-card holders from the apportionment count. The Constitution requires a population count every 10 years. Census totals are used to divide the 435 seats in the House of Representatives among states; those seat allocations also help determine each state’s Electoral College votes. States use additional census data to redraw legislative districts. The proposed exclusion would mark a break with the country’s historical practice of including all residents in the apportionment count, regardless of immigration status. It could reduce the representation of states with larger populations of noncitizens, including people without legal status, while shifting seats and electoral votes to other states. The process involves the Census Bureau, which is overseen by the commerce secretary, followed by the president and Congress. After Congress receives the apportionment figures, states use census data to redraw voting districts. The resulting allocation shapes representation for the decade following the census. President Donald Trump tried to alter the census during his first term but did not succeed. The renewed proposal is expected to prompt legal challenges over who can be counted and how the constitutional requirement to count the population should be applied.