Joe Biden scored decisive victories in all three major Democratic primaries on Tuesday, earning him a nearly insurmountable lead over rival Bernie Sanders in their race for the party's presidential nomination.
As the US grappled with combating the spreading coronavirus pandemic, voters handed the former vice president victory in delegate-rich Florida, as well as Illinois and Arizona.
The command performance speaks to the eagerness of many Democrats to coalesce around a moderate flag bearer, to challenge Republican President Donald Trump, after several other candidates dropped out of the contest in recent weeks and endorsed Biden.
In Florida, the 77-year-old won 62% to 23% against Sanders, a 78-year-old self-described "democratic socialist" senator from Vermont.
Biden was ahead by 23 percentage points in Illinois, with 89% of precincts reporting.
And in Arizona, where polls closed last, Biden was coasting to a third definitive win - and his 19th victory in the last 24 contests.
"Our campaign has had a very good night," Biden said in televised remarks from his home in Delaware.
"We've moved closer to securing the Democratic Party's nomination for president, and we're doing it by building a broad coalition that we need to win in November."
By all accounts it is an astonishing reversal of fortune for Biden, whose campaign was left for dead just one month ago after poor showings in early voting states.
But following a string of victories in high-profile contests starting with South Carolina in late February, and continuing into his show of strength Tuesday, Biden now has a commanding lead in the all-important race for the delegates needed to become the nominee.
Political analyst David Axelrod tweeted that no Democrat has ever come back from a deficit like this, in reference to Sanders.
On Tuesday Biden's delegate count stood at 1 147 compared to Sanders's 861, according to a New York Times rolling tally. A candidate needs 1 991 delegates to secure the Democratic nomination and face Trump in the November election.
Sanders delivered a 20-minute speech online Tuesday. But he did not mention the primaries, focusing instead on his recommendations for addressing the coronavirus pandemic, including injecting $2 trillion in funding to prevent deaths and "avoid an economic catastrophe."
A fourth state, Ohio, was scheduled to vote Tuesday, but it postponed its elections until June on orders of Republican Governor Mike DeWine, who told voters to stay home during the escalating public health emergency.