Hours after the Democrats’ presumptive presidential nominee, Joe Biden, was endorsed by former rival Sen. Bernie Sanders, the former vice president easily cruised to a victory in Wisconsin’s controversial primary that was held amid the coronavirus pandemic.

Fox News projected Monday night that Biden would win soon after Wisconsin election officials started releasing results, one week after in-person voting in the primary took place.

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And in a major upset, an incumbent state Supreme Court justice whom President Trump had backed was defeated by a liberal challenger.

Wisconsin election officials started reporting results after 4 p.m. CT Monday, the deadline implemented by a U.S. Supreme Court ruling for absentee ballots postmarked by last Tuesday’s primary to be received.

With more than 90 percent of precincts reporting, the former vice president had a lead of more than two-to-one over the populist firebrand senator from Vermont. Sanders ended his White House bid last Wednesday, the day after the primary. He backed Biden earlier Monday.

But, the Democrats’ presidential primary contest – in which 85 convention delegates have been up for grabs – was far from the only race on the ballot. There were numerous municipal general elections, including in Milwaukee, the state’s largest city. And, there was a crucial contest for the Wisconsin Supreme Court, where conservative-aligned justices had a 5-2 majority over progressive justices. With more than 90 percent of precincts reporting, challenger Jill Karofsky lead incumbent Daniel Kelly – whom Republican ex-Gov. Scott Walker appointed – by nearly percentage points.

Kelly, the first incumbent justice to lose an election in a dozen years, congratulated Karofsky in a statement.

Karofsky, in video comments from her home, decried the holding of in-person voting last week during the pandemic, saying, "anyone who wasn't brought to tears when they were looking at those people in Milwaukee voting on Tuesday, and voting in Green Bay on Tuesday, just doesn't have a heart."

Outside groups shelled out some $5 million to run ads in the state Supreme Court election. While Kelly lost, conservative justices will still have a 4-3 majority on the highest court in the crucial general election presidential battleground state that President Trump narrowly carried four years ago, helping him win the White House.

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In a tweet earlier this month, Trump touted Kelly, saying he’s “Tough on Crime, Loves our Military and our Vets. He has my Complete Endorsement!”

After a partisan battle that raged from Wisconsin to Washington, D.C., the state last week became the first in the nation to hold in-person primary voting during the height of the coronavirus pandemic.

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

The governor’s 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 before the Republican-dominated state Supreme Court overturned it the evening before the vote.

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The partisan fight over the election – an initial skirmish for a brewing larger national showdown over voting rights – extended all the way to Washington. On the eve of the primary, the U.S. Supreme Court 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 refused to show up over health concerns, forcing many cities and towns to cut the number of polling stations. Milwaukee was down to just five polling sites from the original 180.

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Even though the National Guard stepped in to provide some assistance, long lines instantly formed as the polls opened, with many voters waiting hours to cast a ballot. In many instances, social distancing was extremely difficult to maintain.

Democrats in Wisconsin and across the nation decried the rulings to carry on with the in-person voting during the pandemic.

Biden, in a video tweeted out on Monday night following the release of the results, praised state and local election officials for carrying out their duties in "the most difficult of circumstances."

"It should have never come to that," he added. "No one should ever have to choose between their health and our democracy. Instead, we saw Republicans willing to risk people's lives for thieir own politcial purposes, refusing to work with the governor to find an alternative solution to in person voting last week."

But in the week leading up to Wisconsin's primary, while Sanders called for the election to be delayed, Biden didn't weigh in and instead said the decision was up to Wisconsin officials.

Fox News' Madeleine Rivera contributed to this story