Democratic presidential candidate Joe Biden has widened the gulf between him and rival Bernie Sanders in primary elections held in Florida, Illinois and Arizona.
Accelerating his momentum in the race, the former US vice-president made a clean sweep in all three states. Mr Biden appealed for support directly to Sanders supporters.
With his hat-trick, Mr Biden took another big stride towards becoming the Democratic candidate who will face President Donald Trump in November.
Mr Biden won a smashing victory over Mr Sanders in Florida, the biggest prize of the night with 219 delegates. The former vice-president won 62% of the vote and about 130 delegates. Mr Sanders, with only 23%, took some 48 delegates, with the rest still to be distributed.
Mr Trump won that traditional battleground state by 1.2 percentage points in the 2016 presidential election. In Illinois, with most precincts reporting, Mr Biden led the Vermont senator by 59% to 36%.
With most votes counted in Arizona, Mr Biden has a double-digit lead over Mr Sanders in the south-western state.
A Democratic candidate needs 1,991 delegates to clinch the nomination. On the eve of Tuesday’s vote, Mr Biden was hoping to build on his victories in 16 of the last 21 state contests.
The former US vice-president’s triumph last month in South Carolina – his first ever primary win over three campaigns for president – resuscitated his faltering campaign.
According to opinion polling, most voters said electability was a priority for them.
About three in four Florida voters said Mr Biden would have a better chance of beating Mr Trump, a Republican. Just one in five said the same of Mr Sanders. Older voters were more likely to say they supported Mr Biden.
Nearly half of Florida’s voters said Mr Sanders’ stances were too liberal. In a webcam speech from his home in Wilmington, Delaware, to comply with US anti-coronavirus advice against public gatherings, Mr Biden appealed to Mr Sanders’ passionate supporters.
He said: “Let me say, especially to the young voters who have been inspired by Senator Sanders, I hear you, I know what’s at stake, I know what we have to do.”
But he focused largely on the outbreak sweeping the US, striking a unifying tone as he said: “The coronavirus doesn’t care if you’re a Democrat or a Republican… we’re all in this together.”
Mr Sanders hosted an online address from Washington DC, but he did not drop any hints about the future of his campaign.
He instead talked about the coronavirus crisis, outlining proposals to address the pandemic, which he said would cost some $2tn.
Democrats in three states have just cemented the presidential nomination for Joe Biden.
Bernie Sanders was soundly defeated in Illinois and Arizona and routed in Florida, where in one county he finished third behind Michael Bloomberg, who dropped out weeks ago.
He will fall even further behind in the national convention delegate count, as the primary season appears to be heading towards suspended animation, with multiple states delaying their contests until June.
Mr Sanders should have a long think about how long he wants to stay in this fight, even if he does have more than enough financial resources to carry on.
He is going to face growing calls from Democrats to gracefully bow out – something he did not do until the eve of the convention four years ago, much to the consternation of many Hillary Clinton supporters.
The bottom line for Mr Sanders may be evaluating what’s best for the movement he created. Will staying in the race give him a continuing platform to talk about his issues and buy him time for a potential comeback? Or will hanging around only increase the chances that he is relegated to an electoral afterthought?
Also on Tuesday night, the US president officially clinched the Republican party nomination with a win in the Illinois primary.
His victory had been a foregone conclusion in a contest where he has faced only nominal opposition from a former Massachusetts Governor, Bill Weld. Illinois’ delegates drove Mr Trump over the 1,276-delegate threshold required to become the party’s standard-bearer.
Republican National Committee Chairwoman Ronna McDaniel congratulated the president on Twitter for “officially becoming the presumptive Republican nominee”.