In Hawaii, Illinois and Vermont, voters who haven’t registered yet will be able to on Election Day, right before they cast a ballot. In Indiana, Mississippi and Georgia, the registration deadline is now weeks past, and registered voters who turn up will have to show a photo ID.

Their states, and many others, have been moving over the past decade in starkly different directions. Some, predominantly blue, have expanded early voting, or made registration simpler or even automatic, in a bid to make voting as painless as possible. Other states, mostly red, have curtailed the election calendar or adopted strict ID laws that can have the opposite effect.

As a result, voters’ experiences in the same national election will vary significantly by state, to a greater degree than has been true in decades. Underlying that reality is an increasingly partisan split over whether it should be a goal at all in America to get more people to vote.

Many political scientists say that policies that make voting easier would also make American democracy more representative and less likely to favor the interests of wealthier, older and white voters who typically turn out at higher rates. Broader participation, proponents say, could ease polarization, lift faith in government and dampen criticism that politicians representing the views of a minority of Americans wield the majority of power in Washington.