A unanimous Supreme Court ruled Monday that states can count everyone, not just eligible voters, in deciding how to draw electoral districts.

The justices turned back a challenge from Texas voters that could have dramatically altered political district boundaries and disproportionately affected the nation’s growing Latino population.

The court ruled that Texas’ challenged state Senate districting map, using total population, complied with the principle of “one person, one vote,” the requirement laid out by the Supreme Court in 1964 that political districts be roughly equal in population.

A unanimous Supreme Court ruled Monday that states can count everyone, not just eligible voters, in deciding how to draw electoral districts.

The justices turned back a challenge from Texas voters that could have dramatically altered political district boundaries and disproportionately affected the nation’s growing Latino population.

The court ruled that Texas’ challenged state Senate districting map, using total population, complied with the principle of “one person, one vote,” the requirement laid out by the Supreme Court in 1964 that political districts be roughly equal in population.