But the state Supreme Court ultimately ruled that Evers did not have the authority to postpone the election after the legislature challenged his order. That meant in-person voting happened as planned, even though some counties were not able to staff anything near their normal number of voting locations. Municipalities across the state had to scramble to run an in-person election, with many closing polling places and National Guardsmen being drafted to serve as poll workers in most of the state’s counties.

In Milwaukee, the biggest city in the state, just five of 180 planned precincts were open on Tuesday, as volunteer poll workers dropped out due to concerns about coronavirus.

The U.S. Supreme Court also ruled that ballots had to be postmarked by Election Day and received by 4 p.m. local time on Monday, adding another complicated wrinkle to the election. In Wisconsin, ballots must typically be returned to clerks by 8 p.m. on Election Day, regardless of when they’re postmarked.

Municipalities had to determine how to interpret the postmark ruling for ballots that didn’t have a postmark or had an unclear one, which could become another possible subject of post-election litigation.

The battles in Wisconsin foreshadow the political and legal fights set to play out across the country before the November general election. Both Democrats and Republicans are standing up significant operations to fight over voting laws in the states.

And Trump, in particular, has taken a hard-line stand against mail voting. He has said, baselessly, that mail balloting will lead to widespread voter fraud.

In the Democratic presidential primary, Joe Biden claimed victory over Bernie Sanders by a wide margin, the Associated Press declared early Tuesday. Sanders dropped out of the race on Wednesday, the day after in-person voting in the state, and endorsed the former vice president on Monday .