Polls are open and long lines have already formed in urban areas in Wisconsin as the state becomes the first in the nation to hold in-person primary voting during the height of the coronavirus pandemic.

Voting got underway on Tuesday, hours after a fierce political battle between state Republican leaders and Democratic Gov. Tony Evers, who twice attempted to postpone in-person voting and extend the ability to cast ballots by mail.

The governor’s Monday executive order – following an urgent warning by mayors from Wisconsin’s largest cities that “hundreds of thousands of citizens at risk by requiring them to vote at the polls while this ugly pandemic spreads” – drew instant pushback from the GOP-controlled state legislature and was overturned on the eve of the primary by the Republican-dominated state Supreme Court.

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The partisan fight over the election – which is an initial skirmish for a brewing larger national showdown over voting rights – extended all the way to Washington, D.C., where the U.S. Supreme Court on Monday night struck down a federal district court’s ruling allowing a weeklong extension to return absentee ballots. The ruling by the high court broke along ideological lines, with the five judges appointed by Republicans winning out over the four appointed by Democrats.

With the state under a stay-at-home order, thousands of poll workers indicated they wouldn’t show up on Tuesday, forcing many cities and towns to cut the number of polling stations. Milwaukee was down to just five polling sites from the original 180. Lines could be long in many of the state’s cities, which will make social distancing extremely difficult to maintain.

Reporters at polling locations in urban and suburban areas tweeted pictures of long lines forming as voting got underway.

The National Guard stepped in to provide some assistance, distributing hand sanitizer and other supplies to polling stations across the state.

The state’s elections commission urged voters to “keep your face-to-face interactions brief with both poll workers and other voters. We want to limit the risk for everyone in the process on Election Day.” And the elections commission noted that “curbside voting options are available” for those who are ill and need to vote.

“Because of poll worker shortages, your polling place may have changed due to consolidation,” warned the elections commission, which urged voters to check the state elections website before heading out to vote.

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The top two Republicans in the state – House Speaker Robin Vos and Senate Majority Leader Scott Fitzgerald – emphasized Monday night that “the safety and health of our citizens have always been our highest concern.”

They added that “citizens should be able to exercise their right to vote at the polls on Election Day, should they choose to do so.”

But Democratic Lt. Gov Mandela Barnes, firing back Tuesday, tweeted “Good morning and welcome to the Shit Show! Today’s episode has been produced by the Supreme Court and directed by the incomparable Speaker and Senate Majority leader duo.”

Hours later, the governor tweeted that although he remains "deeply concerned about the public health implications of voting in-person today, I am overwhelmed by the bravery, resilience, and heroism of those who are defending our democracy by showing up to vote, working the polls, and reporting on this election."

On the ballot in Tuesday’s election – the Democratic presidential primary between clear front-runner Joe Biden and Sen. Bernie Sanders.

Biden has held the clear lead going into the contest. The chorus of calls for Sanders to end his White House bid and back Biden will only grow louder if Sanders suffers another defeat in Wisconsin – a state that the senator easily won over eventual nominee Hillary Clinton in the 2016 primary.

Sanders had repeatedly urged that the primary be delayed due to health concerns.

“Let's be clear: holding this election amid the coronavirus outbreak is dangerous, disregards the guidance of public health experts, and may very well prove deadly. For that reason, our campaign will not be engaged in any traditional GOTV efforts,” he tweeted Monday night.

Biden’s declined to take a stand and instead has deferred to Wisconsin officials. Last week he told reporters “I think you could hold the election as well dealing with mail-in ballots and same-day registration.”

“I think it’s possible to do both, to have both more mail-in ballots” he added. “I think it could be done ... but that’s for them to decide.”

There’s a lot more at stake on Tuesday’s ballot for Wisconsin voters than just the presidential primary contest. There’s an important battle for a Wisconsin Supreme Court seat that could influence general election voting rules in the crucial presidential battleground state that President Trump narrowly carried four years ago, helping him win the White House.

Trump weighed in on the controversial primary, noting the state Supreme Court’s decision and urging voters to support the incumbent justice who’s up for re-election – and who sat out Monday’s ruling by the state’s highest court.

Also on the ballot on Tuesday are mayoral general elections in numerous municipalities including Milwaukee, the state’s largest city.

Wisconsin residents have been urged for weeks to vote by absentee ballot, which led to a tidal wave of demand for vote-by-mail ballots. Election officials reported on Sunday that they received 1,268,587 absentee requests and that 1,256,474 absentee ballots had been sent to voters. They reported that 703,048 ballots had been returned.

But thousands of people who requested ballots but will not receive them in time for their ballots to be returned by Tuesday night. The U.S. Supreme Court ruling that the federal district court judge exceeded his authority last week when he allowed for absentee ballots to be counted through April 13 means that people still waiting for absentee ballots will be forced to choose between voting in person or skipping the election.

One thing that is delayed — the results. The Supreme Court let stand federal district court Judge William Conley’s order that results wouldn’t be counted for another week.

Wisconsin is the only state that was scheduled to hold a primary in April that has gone forward with in-person voting. The other states either delayed their contests until May or June or are holding them nearly entirely by mail.