WASHINGTON (REUTERS) - Joe Biden is starting to get the help he needs to compete with President Donald Trump's massive election war chest, although the Democrat has a huge shortfall to make up in the coming months.

Former Barack Obama staffers are planning to raise money for the putative Democratic presidential nominee.

Former rivals like Senator Elizabeth Warren are using their donor lists on Mr Biden's behalf, and the former vice-president's campaign could soon strike a deal with the Democratic National Committee that would allow it to rake in much larger donations.

Those are positive signs for a campaign that has worked furiously to figure out ways to bring in cash since the coronavirus pandemic put millions of Americans out of work and forced the 2020 White House race into a digital-only environment.

Even with the newfound support, Biden remains at a significant financial disadvantage heading into the Nov 3 election against Mr Trump, a prodigious fund raiser who has been raising money for the general election since 2017.

"I think right now it's very hard to raise money," said Mr John Morgan, a trial lawyer from Florida and a long-time political donor. "People don't know if they're financially ruined or not yet."

The Trump campaign and the Republican National Committee (RNC) said this week they had raised a whopping US$212 million (S$300 million) this year, giving the President US$240 million in cash in hand.

Mr Biden's campaign has yet to announce its fund raising total for March. It had about US$12 million on hand as of Feb 29, before his decisive victories in Democratic nominating contests.

Mr Biden was not a fund-raising juggernaut even before the Covid-19 outbreak upended politics, finding real success only in the closing months of the Democratic presidential race.

His campaign is now hoping that endorsements this week from his one-time boss, Mr Obama, as well as former rivals Bernie Sanders and Warren, will give its fund raising a shot in the arm, helping the campaign access a wider network of deep-pocketed donors.

Mr Biden told donors on Thursday the backing from his former competitors helped him bring in US$5.25 million over two days this week.

Mr Obama's former finance chair, Mr Rufus Gifford, who helped his 2012 campaign collect more than US$1 billion, is setting up an online fund-raising event on May 1 for Mr Biden involving officials who worked for the former Democratic president.

"The goal will be to re-assemble the team that propelled the Obama/Biden team to victory twice," Mr Gifford wrote in a recruitment e-mail seen by Reuters.

US Senator Kamala Harris, a former White House rival and a strong contender to be Mr Biden's vice-presidential pick, participated in an online fund raiser for Mr Biden last week that brought in US$150,000 - exceeding the event's US$100,000 target, said event co-host Kimberly Marteau Emerson, a principal at KME Consulting.

Mr Biden's campaign also plans to host a series of virtual events in the coming weeks featuring celebrities such as Broadway star Kristin Chenoweth, singer Melissa Etheridge and tennis great Billie Jean King, as well as former candidate Cory Booker and former Secretary of State Madeleine Albright, said Mr Tom Sacks-Wilner, who serves on Mr Biden's finance committee.

Mr Sanders, who amassed a huge grassroots army of supporters, has not committed to raising funds for Mr Biden.

A SHIFTING CONVERSATION

Mr Alan Kessler, a Philadelphia attorney who has held several events for Mr Biden, said the campaign was reluctant to ask people for money in the early stages of the pandemic, which has plunged the US economy into the sharpest downturn in decades.

That is beginning to change, he said.

"We're starting to be able to move on to the next phase, which is actually being able to comfortably reach out to people," he said.

Mr Trump's handling of the government response to the crisis has helped fuel donations, said Mr Sacks-Wilner.

"It's been kind of a boon for the campaign because we have been able to raise as a result of what is seen to be lack of leadership," he said, noting some independent donors were reaching out directly to him.

The Trump campaign said that support remained enthusiastic for the President.

"The people know that President Trump is fighting for them, so they are fighting for him as well," said Trump campaign manager Brad Parscale.

Now that Mr Biden is the expected nominee, his campaign is discussing a joint fund-raising agreement with the DNC, according to two people familiar with the talks.

Such an accord would likely result in the formation of an entity that could receive six-figure sums from wealthy donors rather than the US$5,600 that campaigns can accept for the primaries and general election. Mr Trump has long had a similar arrangement in place with the RNC.

Mr Biden's candidacy will also be aided by a bevy of super PACs that can receive unlimited contributions but cannot coordinate efforts with the campaign.

The extent of support from another source, billionaire Michael Bloomberg, is not yet known. After he spent more than US$800 million of his money pursuing his own presidential bid, the former New York mayor endorsed Mr Biden and appeared to have plans to form an independent organisation that would fulfill his vow to put his US$60 billion personal fortune towards helping elect the Democratic presidential nominee.

But Mr Bloomberg said later he would send US$18 million of leftover campaign funds to the DNC instead for operational efforts.

Advisers say he could still spend more in the coming months, pointing to the more than US$100 million he donated to Democrats during the 2018 congressional elections as an example of his readiness to help the Democratic cause.

"We're looking at how to best support Democratic victories up and down the ballot in November, just as Mike Bloomberg has done in previous cycles," a Bloomberg spokesman said.

Mr Morgan, the Florida lawyer, remains sceptical that Mr Biden can raise large amounts in the short term, arguing that online fund raising is no substitute for the real thing.

"It's like going to the zoo," Mr Morgan said. "Do you want to go to the zoo, or do you want to go to the virtual zoo? I want to see the giraffe in person."