A new poll of Democratic primary voters shows a significant consolidation of support behind former vice-president Joe Biden, emphasising Senator Bernie Sanders's failure to broaden his support.
Among those Democrats who have voted or plan to vote, 61pc say Mr Biden is their preferred nominee, as opposed to 32pc who prefer Mr Sanders.
In a poll conducted in mid-February, 15pc of voters identified Mr Biden as their preferred choice.
His swift transformation into front-runner followed a decisive win in South Carolina, at which point multiple candidates who had been splitting the loyalties of the electorate dropped out and endorsed him.
But even after fellow liberal Senator Elizabeth Warren dropped out of the race last week, Mr Sanders's support jumped only five points, to 32pc, in a smaller field.
The poll also underscored Mr Biden's support with one of the most crucial groups within the Democratic Party, black voters, who said they prefer him to Mr Sanders, by 77pc to 18pc.
On Sunday, Mr Biden unveiled a proposal to make public college free for families who earn less than $125,000 (€112,000) a year, part of his campaign's broader effort to court younger and more liberal voters.
He has also said he wants to invest $70bn (€63bn) in historically black colleges and minority-serving institutions. Free college tuition has been a staple for Mr Sanders.
Last Friday, Mr Biden adopted a bankruptcy plan, which would make it easier for people to go through the bankruptcy process and would allow student loan debt to be discharged like any other debt.
Both candidates have significantly scaled back campaign events in recent days in response to the outbreak, cancelling mass gatherings in favour of online events.
Those decisions come as some states consider whether to hold votes at all. Already, Louisiana and Georgia have announced they will postpone their primaries. (© Washington Post)