Joe Biden won the Florida and Illinois primaries Tuesday, taking two big strides toward clinching the Democratic presidential nomination on an election day shadowed by the coronavirus pandemic.
The former vice president prevailed over Vermont Sen. Bernie Sanders in convincing fashion, forging a now-familiar coalition of party moderates, older and electability-minded voters and African Americans.
In all, 441 delegates were at stake in a day when Arizona also cast its ballots.
It takes 1,991 to win the nomination at the party's summer convention and Biden's powerful showing leaves Sanders with only the barest hopes of a comeback.
Ohio postponed its primary hours before the polls were set to open after the state's health director, acting at the behest of Gov. Mike DeWine, declared a public health emergency. Even so, some voters turned out only to find their usual polling place locked up tight.
Where voting was underway, election officials worked to balance safety with business as usual.
In Illinois, Cook County Clerk Karen Yarbrough urged poll workers to use painter's tape to mark the floor in 6-foot increments, so those in line would stand far enough apart to avoid spreading the virus. "This picture can save lives," she said in how-to instructions posted on Twitter.
Still, there were reports of missing disinfecting supplies, shuttered voting centers that were supposed to be open and other mishaps throughout the country.
The crisis surrounding the coronavirus introduced an element of uncertainty into a contest that has seemed largely settled since Biden roared back from the brink of elimination with a crushing victory in last month's South Carolina primary and a string of Super Tuesday victories on March 3.
It is not so much the mathematics of the race, which weigh heavily in Biden's favor, but rather the mechanics: With tens of millions of Americans locked down at home, several states have delayed their upcoming contests, leaving the candidates and their campaigns in an unprecedented limbo.
After Tuesday, no voting is scheduled until Puerto Rico's March 29 primary _ and officials there are seeking a delay _ so it was unclear how the contest would proceed. (Ohio allowed mail balloting to continue, with plans to open its polls and tally the results June 2.)
The chairman of the Democratic National Committee, Tom Perez, urged states that had yet to hold primaries to expand their vote-by-mail programs, absentee balloting and polling station hours to avoid further disruptions.
"The right to vote is the foundation of our democracy, and we must do everything we can to protect and expand that right instead of bringing our democratic process to a halt," Perez said in a written statement.
The balloting Tuesday was marked by confusion and lower in-person turnout than expected as the usual election day miscues were compounded by uncertainties caused by the country's unprecedented health crisis.
Ami Gandhi, senior counsel at the Chicago Lawyers' Committee for Civil Rights, said the group was fielding an unprecedented volume of calls from voters confused about where to vote or unsure whether they should leave their homes to cast ballots.
"If it wasn't so tragic, it would be comical, the numbers of errors we're seeing today," Gandhi said.
Some poll workers failed to show up in Florida, leaving election officials scrambling to accommodate voters with no place to register their preference. (Nearly 1.1 million ballots had been cast early or mailed in ahead of election day.)
Makeshift polling places had to be set up in all three states, as nursing homes and other locations that typically serve as polling places were closed off to avoid large gatherings.
The two candidates took differing stands on whether the balloting should proceed under such extraordinary circumstances _ a reflection, perhaps, of Sanders' desire to prolong the contest and Biden's eagerness to wrap it up.
"We are not doing traditional (get out the vote) outreach in states holding primary contests today," Mike Casca, a Sanders spokesman, said after the candidate suggested delaying the election. "We are making clear to voters that we believe going to the polls amid the coronavirus outbreak is a personal decision and we respect whichever choice they make."
The Biden campaign cited the heavy early vote, and said that whatever happens Tuesday, overall turnout is not expected to fall dramatically.
"The American people are resilient and strong," deputy campaign manager Kate Bedingfield wrote in an election day memo. "We have maintained our democracy through war and peace, economic (downturn) and prosperity, and in previous moments of public health crisis ... We are confident that we can meet that same challenge today and continue to uphold the core functions and values of our democracy."
Biden entered Tuesday with a sizable lead in the delegate count, 898 to 745 for Sanders, according to The Associated Press. While not insurmountable, that gap is formidable, given rules that award delegates on a proportional rather than winner-take-all basis. To overtake Biden, Sanders would have to start winning one landslide victory after another, a reversal of fortune even more dramatic than Biden's never-before-seen turnaround.
Sanders lost Arizona, Florida and Illinois to Hillary Clinton four years ago, and polls headed into Tuesday's election showed him trailing Biden in all three.