Which case allowed states to redraw legislative district boundaries as long as each district contains approximately the same population?

Baker v. Carr is significant because it established the principle of "one person, one vote," which mandates that legislative districts must contain approximately equal populations. This landmark decision was a pivotal moment in addressing the issue of malapportionment, where some districts had disproportionately larger or smaller populations than others. The ruling allowed federal courts to intervene in redistricting disputes, leading to a more equitable representation in state legislatures. The case effectively enforced the idea that individual citizens' votes should carry equal weight in legislative representation, thus playing a crucial role in shaping modern electoral processes. The other cases mentioned deal with different aspects of election law and campaign finance and do not apply to the issue of legislative district boundaries.