While much of the attention last week was focused on U.S. Supreme Court decisions on gay marriage, election geeks in Minnesota were pondering the “other” bombshell dropped by the court.

That case, Shelby County v. Holder, carries echoes of the civil rights movement, a time when advocates of “states’ rights” battled federal intervention. In a 5-4 ruling, the court’s conservative majority declared unconstitutional a pillar of the Voting Rights Act of 1965. Then, as now, it was the South (Shelby County, Alabama) vs. the feds (U.S. Attorney General Eric Holder.)

But this time, it was the South’s success in attracting minority voters, and not old schemes for keeping black voters away, that carried the day. Minnesota and most northern and western states were not directly affected by the ruling, but the touchy issue of voting and civil rights strikes a chord everywhere.

“We have common interest in the election laws and election processes throughout the U.S.,” said Joe Mansky, head of the Ramsey County elections office. “For those of us who are not part of the jurisdiction covered by Section 5, we want to make sure we never are.”

Section 5 is the part of the act that puts states and counties with a history of voting discrimination under federal oversight. Those states — including Texas, Alabama, Mississippi, Louisiana, South Carolina and Virginia — must submit any election-law changes to the U.S. Department of Justice or a courts panel for “pre-clearance” before putting them into effect. The Shelby decision held that the old formula for determining which states require oversight is unconstitutional. Barring a highly unlikely congressional decision to rewrite the law, the idea of special oversight appears dead.

In the decision, Chief Justice John Roberts argued that the Voting Rights Act has succeeded so well in the South that special attention is no longer needed. “Things have changed dramatically,” he said of the South — equal turnout and registration rates among white and black voters, unprecedented numbers of minority officeholders and no more “blatantly discriminatory” evasions of federal orders.

One aspect that links the case with Minnesota concerns voter ID — the politically charged requirement that all voters show photo identification at the polls.

Minnesota rejected voter ID in the election last November. Southern states, mostly GOP-controlled, have embraced it. But Section 5 and Holder stood in their way because of the fear that minority voters without the required IDs would be disenfranchised. “Pre-clearance” was a problem then; after the Shelby decision, voter ID will likely spread.

On Tuesday, Texas Secretary of State John Steen cited the Supreme Court decision in announcing that his state’s voter ID law — which a federal appeals panel once rejected for imposing “strict, unforgiving burdens” on the poor and racial minorities — was henceforth in effect.

The Voting Rights Act of 1965 remains a monument to civil rights, and it is still illegal for states and local elections officials to discriminate based on race. But actual discrimination will now have to be litigated after it happens.

A postscript to the ruling was provided by Minnesota Secretary of State Mark Ritchie. He said the lesson learned in Minnesota during the voter ID battle is that major election-law changes must have broad bipartisan support. But the court’s 5-4, conservative-liberal split this week was as divided as Minnesota’s GOP-DFL split over voter ID.

“Most people would like to see something other than deeply divided partisan decisions on elections,” Ritchie said.