Volunteers wearing protective masks and gloves assist a voter at an early voting ballot drop off location in Milwaukee, Wisconsin, U.S., on Thursday, April 2, 2020.

The Supreme Court voted 5-4 on Monday to reverse an order extending the absentee ballot deadline for voting in the Wisconsin elections scheduled for Tuesday, stepping into a back-and-forth between Democrats and Republicans in the state over when voting would take place.

Gov. Tony Evers, a Democrat, signed an executive order suspending in-person voting in the state earlier on Monday after trying and failing to convince the GOP-dominated state legislature to postpone elections until May. His order was blocked by the Wisconsin Supreme Court in the evening.

The Supreme Court, which was considering a case brought before Evers issued his executive order, was not considering whether voting would take place on Tuesday, but only whether to keep in place an order that extended the deadline for absentee ballots to be postmarked.

In an unsigned order from which the court's four liberal justices dissented, the court did away with the extension.

The top court's five Republican-appointees, none of whom attached their name to the court's order, reasoned that extending the date by which voters could mail absentee ballots "fundamentally alters the nature of the election."

"Wisconsin has decided to proceed with the elections scheduled for Tuesday, April 7. The wisdom of that decision is not the question before the Court," the order reads. "The question before the Court is a narrow, technical question about the absentee ballot process."

The case is the first dispute over COVID-19 to reach the justices.

Democrats and voting rights groups had gone to court to push for an extended deadline, warning that coronavirus fears could keep voters from the polls. On Friday, a federal appeals court upheld a one-week extension for absentee ballots.

Republicans asked the Supreme Court to halt that order, issued by the 7th U.S. Circuit Court of Appeals.

"A last-minute change to a voter deadline carries an increased risk that voters will not appreciate when votes actually must be cast," Patrick Strawbridge, the attorney for the Republicans, warned in a filing with the top court. Strawbridge wrote the Supreme Court should "maintain the status quo of state election laws."

In response, Democrats said that Republicans were ignoring the health risks posed by coronavirus, which has sickened more than 2,000 in the state, according to data from local health authorities.

"The 'electoral status quo' already has been upended ― not by any judicial order, but by the COVID-19 pandemic and the 'voter confusion and electoral chaos' it is causing," wrote Marc Elias, an attorney for the Democrats, in a brief submitted to the court.

"Until very recently, Wisconsin voters reasonably expected they would be able either to vote safely in person on election day or through a reliable, well-functioning absentee ballot system," Elias wrote. "Now they cannot ― and not because of any court order, but because of the pandemic."

The order from the Supreme Court puts a heavy emphasis on the fact that the date for the ballots to be postmarked — not just received by elections officials — had been extended. That remedy went beyond what Democrats had even sought, the court wrote.

"By changing the election rules so close to the election date and by affording relief that the plaintiffs themselves did not ask for in their preliminary injunction motions, the District Court contravened this Court's precedents and erred by ordering such relief," the Supreme Court wrote.

"This Court has repeatedly emphasized that lower federal courts should ordinarily not alter the election rules on the eve of an election," the order reads.

Justice Ruth Bader Ginsburg called the majority's decision "ill advised" in a dissent joined by Justices Sonia Sotomayor, Stephen Breyer and Elena Kagan.

"While I do not doubt the good faith of my colleagues, the Court's order, I fear, will result in massive disenfranchisement," Ginsburg wrote. "A voter cannot deliver for postmarking a ballot she has not received. Yet tens of thousands of voters who timely requested ballots are unlikely to receive them by April 7, the Court's postmark deadline."

Wisconsin remains under a shelter-in-place order, signed by Evers, and federal officials have urged Americans not to gather in groups of 10 or more until the end of April.

A dozen states and Puerto Rico, a territory, have postponed elections since the coronavirus pandemic erupted in the United States. The Supreme Court itself has postponed arguments scheduled for its March and April sessions because of health concerns related to the virus.