After a flurry of 11th-hour legal action failed to stop the balloting, Wisconsin voters will head to the polls for a presidential primary and state and local elections on Tuesday despite mounting fears about health risks from the coronavirus.

But officials were uncertain about what to expect and how many voters will turn out as Wisconsin residents, like most people around the country, remain under orders to stay at home and public gatherings are banned during the coronavirus crisis.

Two late court rulings on Monday put the election, which will include Democratic and Republican presidential primaries and voting for thousands of state and local offices, back on track after days of uncertainty.

In deciding separate lawsuits brought by Republicans, the state Supreme Court blocked Democratic Governor Tony Evers' order to delay the election until June and the U.S. Supreme Court overturned a federal judge's decision extending absentee voting, ruling absentee ballots must be postmarked by Tuesday to be counted.

"Now voters will be forced to choose between their health and their right to vote, an untenable choice that responsible public officials tried to avoid," said Satya Rhodes-Conway, the Democratic mayor of Madison, Wisconsin.

The legal maneuvering overshadowed the Democratic presidential primary in Wisconsin, the first nominating contest held since March 17 in the race to pick a challenger to Republican President Donald Trump for the Nov. 3 election.

More than a dozen other states have postponed or revised their nominating contests in an effort to stem the spread of the virus, which also has pushed front-runner Joe Biden and rival Bernie Sanders off the campaign trail.

Biden has built a nearly insurmountable lead over Sanders in the delegates who will pick the nominee at the national convention this summer. The convention, scheduled to be held in Milwaukee, Wisconsin, has been pushed back to August from July by the coronavirus outbreak.

After a late-night meeting on Monday, the Wisconsin Elections Commission said no results of Tuesday's voting would be released until April 13, the deadline for absentee ballots postmarked by Tuesday to be received.

Concerns about the coronavirus have led to a shortage of poll workers in more than half of the state’s municipalities, causing the consolidation of many polling sites and the use of up to 2,400 state National Guard members to assist at the polls.

In Milwaukee, there will be five polling places instead of the usual 180, officials said, leaving the likelihood of crowds and long lines in many locations.

The reduced crews of poll workers will urge voters to follow guidelines on social distancing and hand sanitizing, election administrators said. Voters will line up outside polling places.

But the explosion of court cases, days of uncertainty and mounting health fears offer a potential preview of the November election if the coronavirus outbreak lingers or returns.

In opposing any delay, Republicans cited the potential for voter fraud and the short timeline to fill thousands of state and local offices that are also on the ballot.

Democrats said Republicans wanted to dampen turnout in state races, particularly for a seat on the Wisconsin Supreme Court that could be instrumental in ruling on future voting-rights cases in the battleground state crucial to November's election.

(Editing by Raju Gopalakrishnan) ((John.Whitesides@thomsonreuters.com; 202-898-8300; Reuters Messaging: john.whitesides@thomsonreuters.com))