The remarkable partisan polarization over HR1 — House Democrats’ ambitious but hardly novel package of “pro-democracy” reforms, centered on voting rights — shows that this issue, once a matter of bipartisan do-gooder sentiment, has now become a deadly serious point of contention in our politics. This has happened rather quickly as the two parties each came to recognize their future might depend on expanding or restricting ballot access.

All 234 House Democrats present voted for HR1 while all 193 Republicans present voted against it. That’s remarkable given the bipartisan support voting rights (and even other features of the bill like campaign finance reform) had until very recently. To be sure, politicians in both parties still think ballot access is critically important. But Republicans, having placed their bets on an electoral base that is overwhelmingly white and significantly upscale, are becoming deeply invested in suppression of voting opportunities for those who are unlikely to join their coalition.

A recent study showed that of 20 states identified as making it most difficult to vote, Trump carried 17. Hillary Clinton carried 12 of the 20 states where it is easiest to vote.

The homeland of Republican voter suppression is in the South, where keeping African-Americans from the ballot box is an ancient tradition practiced mostly by Democrats in the long period from the emancipation of slaves until the end of Jim Crow. Now across the region the Republicans who control every state legislature in the former Confederacy are pursuing an ensemble of measures to restrict the franchise, from cutbacks in early voting, to aggressive voter purges, to voter-ID requirements, to reductions in polling places. This trend rapidly proliferated after the 2013 Supreme Court decision (supported by all five Republican-appointed Justices, with all four Democratic-appointed Justices dissenting) that killed the chief enforcement mechanism of the Voting Rights Act of 1965. Without the requirement that states with a history of racial discrimination submit election system changes to the U.S. Justice Department for “preclearance,” it’s been open season on ballot access, particularly as racial polarization in partisan preferences has intensified.