FILE - Democratic presidential candidate former Vice President Joe Biden poses for photos at a primary night election rally in Columbia, S.C., Feb. 29, 2020.

Former U.S. Vice President Joe Biden has taken a commanding lead in the race for the Democratic presidential nomination to oppose Republican President Donald Trump in November's national election. 

Biden, in his third run for the U.S. presidency over three decades, easily defeated Vermont Sen. Bernie Sanders in party primary elections in Florida, Illinois and Arizona on Tuesday, giving him a nearly insurmountable lead in pledged delegates to the party's national nominating convention in July. 

After losing 19 of the last 24 state primary votes to Biden, the Sanders campaign said Wednesday he would be "having conversations with supporters to assess his campaign," but there was no immediate indication that the self-declared democratic socialist was dropping out. 

FILE - Democratic presidential candidate Bernie Sanders walks away from the podium after speaking to reporters in Burlington, Vermont, March 11, 2020.

Instead, Sanders said that in the immediate term he would focus on the government's response to the coronavirus pandemic to ensure "that we take care of working people and the most vulnerable." 

Biden won all three primaries on Tuesday by lopsided margins, taking the battleground state of Florida, Trump's adopted home, by nearly 40 percentage points and Illinois and Arizona by smaller, but still decisive counts. 

With large public political rallies ended in the U.S. because of the threat posed by the coronavirus, Biden declared in a somber, video-streamed address from his home in the eastern state of Delaware, "We've moved closer to securing the Democratic Party's nomination for president." 

Biden, speaking before votes were counted in the western state of Arizona, said he had a broad base of support in Florida and Illinois from African Americans and Latinos, teachers, suburban women, veterans and firefighters. 

WATCH: Biden Scores Decisive Primary Wins in 3 States

Embed

But he also praised Sanders, whose campaign has pushed him to adopt more politically progressive positions on some issues, such as Sanders' call for free tuition at public universities. 

Biden appealed directly to Sanders' young supporters, saying, "I hear you. I know what is at stake. And I know what we have to do. Our goal as a campaign, and my goal as a candidate for president, is to unify our party — and to unify our nation." 

Delegate numbers

A total of at least 1,991 pledged national convention delegates is needed to claim the Democratic nomination. Even with dozens of delegates still to be allocated from the Tuesday voting, Biden holds a 1,147-861 delegate lead over Sanders, with the next major primaries not scheduled until early April. 

FILE - Voter Fred Hoffman fills out his ballot during the primary election in Ottawa, Illinois, March 17, 2020. The polling station was relocated from a nursing home to a former supermarket due to concerns over the outbreak of coronavirus.

Sanders lost the 2016 Democratic presidential nomination to former U.S. Secretary of State Hillary Clinton, who went on to lose to Trump. Sanders has vowed to lead a social and economic revolution, including a massive overhaul of the U.S. health care system with the use of private insurers to pay medical bills to turn it into one fully run by the national government. 

Biden, the former two-term vice president under President Barack Obama, has argued that voters are more concerned about restoring stability and decency to the White House and seeking practical solutions to problems than the dramatic, revolutionary programs Sanders and his progressive allies are espousing.   

Biden said late Tuesday that while he and Sanders may disagree on tactics, they share ground on wanting more affordable health care, reducing income inequality and combating climate change. 

"Senator Sanders and his supporters have brought a remarkable passion and tenacity to all of these issues," Biden said. "Together they have shifted the fundamental conversation in this country."  

Trump narrowly won the key battleground state of Florida in 2016 over his Democratic challenger, former Secretary of State Hillary Clinton, and the populous state is expected to be highly contested again this year.   

FILE - Jefferson County Elections officials arrive to pack up the polling place at Our Lady of Lourdes church in Wintersville, Ohio, March 17, 2020.

Postponed primaries

A fourth state, Ohio in the U.S. heartland, had also been set to hold its primary election Tuesday.

But the state's Republican governor, Mike DeWine, postponed it hours before public voting was set to start in the face of the growing fears of large numbers of voters and poll workers mingling in close proximity with each other at a time when health officials are urging the exact opposite, to safeguard against contracting the deadly coronavirus.   

Ohio is now set to vote in June. It is one of five states, along with Maryland, Georgia, Louisiana and Kentucky, that have postponed a party presidential primary because of the coronavirus pandemic that is causing a historic economic crisis and a shutdown of businesses, schools and sporting events. So far, nearly 6,500 cases of infection and 109 deaths have been reported in the U.S., according to worldometers.info.