These differences would affect how redistricting lines are drawn, in ways political scientists have not yet thoroughly modeled. Daryl Deford, a postdoctoral associate at M.I.T., has generated 50,000 possible redistricting plans for the Texas State Senate. The results using only the citizen voting-age population produced on average some districts that were 50 percent larger than others by total population. Similarly wide disparities appear in hypothetical redistricting for the Arizona and Georgia state senates.

A world where urban districts hold substantially more total population than rural or exurban ones would make some states look more the way they did before a series of landmark court cases in the 1960s that established the principle of “one person, one vote” in state legislatures.

Before the 1960s, many states went decades without redistricting, leaving rural communities overrepresented long after many of their residents had moved to cities. The Supreme Court ruled that states had to regularly reapportion legislative seats to maintain districts of equal size.

The difference wasn’t just semantic. The scholars Stephen Ansolabehere and James Snyder found that after urban areas gained equal representation, more state money flowed toward them, and a leftward shift in state policies followed.

But beyond the implications for redistricting, state budgets or particular policies, there is also a larger question about who should be represented. The framers of the Constitution made clear that everyone counted in apportioning Congress (if not in whole numbers).

But at the time, it was perhaps more obvious why that should be true. The voting population excluded women, children, nonwhites, slaves, immigrants, poor people who owned no land, and plenty of taxpayers. Political maps that counted only white men would have ignored the interests of many people.

The framers of the 14th Amendment reaffirmed this when they debated how to replace the clause that counted slaves as only three-fifths of a person. Some feared that Southern states would block newly freed black men from voting, while still benefiting from their presence in apportionment. They proposed the same idea on the table today, counting only the voting eligible population (a prospect then, as now, that would have required “a true census of the legal voters”).