Joe Biden posted his biggest monthly haul of the campaign in March thanks to his sweeping primary victories, raising $46.7 million as donors consolidated around his candidacy after most of the other Democrats dropped out of the presidential race, new filings show.

As Biden shifts his focus to the general election, he faces a steep fundraising gap with President Trump, who has been raising money for his reelection campaign since 2017. Travel and social-gathering restrictions relating to the novel coronavirus pandemic have added challenges for Biden, as he works to maintain his fundraising momentum as November nears.

These new dynamics were evident in Biden’s March fundraising records. The majority of the money he raised last month came in the first two weeks of March, coinciding with the primary wins that solidified his path to the Democratic presidential nomination. But his fundraising dipped as the campaign went fully virtual to comply with coronavirus social distancing requirements, according to filings released Monday and figures provided by the campaign.

With a virtual campaign, Biden will be tested in his ability to raise money online — one of his biggest fundraising struggles that stands in contrast to Trump, who has an avid and loyal online donor base. Biden’s online fundraising has improved drastically in recent months, and his donors say they are confident the recent endorsements from former president Barack Obama and Sen. Bernie Sanders (I-Vt.) will help generate online donations.

In an email to supporters Monday night, Biden acknowledged he probably will not keep up the fundraising pace this month as the global pandemic halted the momentum generated by his victories in March. And he said he recognized the challenges ahead.

“[Trump] has a lot more money than us, and we are facing an uphill battle trying to catch up now,” Biden said in his note to supporters Monday night.

The Biden campaign entered April with $26.4 million, filings show. The Democratic National Committee and its affiliated fundraising committee, which raises money for the national and state parties, had another $42 million on hand, filings show.

Meanwhile, the Trump campaign, the Republican National Committee and their affiliated fundraising committees have raised more than $1 billion toward the president’s reelection, including $212 million in the first three months of 2020, and entered April with roughly $244 million in cash on hand, filings show.

Still, Biden raised more money in the month of March than the previous two Democratic nominees did in the same month of those presidential election years — a sign of the Democratic donor enthusiasm for November. After some technological glitches shifting to an online-only fundraising schedule, donors said Biden and his campaign are settling into the new format.

“This has been the best response I’ve ever had to any fundraising letter I’ve sent out [than] I have for 30, 40 years,” said Bill Singer, a Democratic donor and member of Biden’s national finance committee, of a coming virtual fundraiser aimed at Chicago-area donors. “The people I’m talking to may have been for [Elizabeth] Warren, may have been for [Pete] Buttigieg, may have been for [Amy] Klobuchar or even [Kamala] Harris, but all that is behind them. They’re all saying, ‘We’re all in for Joe. He’s the nominee. We have to beat Trump. We have to do it.’ ”

The Democratic National Committee raised $32.5 million in March, more than half of which came from leftover presidential campaign funds donated by billionaire Mike Bloomberg. Bloomberg, who ran the biggest self-funded campaign in U.S. history, gave over $1 billion to his campaign, which lasted three months. The Democratic Grassroots Victory Fund raised $2.5 million in March.

Biden and Trump are backed by super PACs, which are independent groups that raise and spend unlimited sums to try to influence elections. Super PACs supporting Biden and Trump are already spending millions running ads on television and online, largely aimed at voters in swing states that will be crucial in November.

The Biden campaign is grappling with divisions in the high-dollar donor community, after Biden distanced himself from the super PAC that helped him through the primaries in favor of a group that worked to support Hillary Clinton and Obama.

In March, major donors began lining up behind the Democratic super PACs supporting Biden, whose latest records were released Monday night.

Among the biggest donors to the pro-Biden super PAC Unite the Country in March were billionaire hedge fund manager James Simons ($3 million); Stewart Bainum, chairman of Choice Hotels International ($2 million); Deborah Simon, philanthropist and daughter of Simon Property Group co-founder Melvin Simon ($500,000); and Seth Klarman, a Boston hedge fund billionaire and former GOP donor ($500,000).

Priorities USA Action, a pro-Biden Democratic super PAC, received its biggest donations in March from the LCV Victory Fund ($2 million) and $500,000 each from three labor unions: AFSCME, Service Employees International Union and the American Federation of Teachers.

The pro-Trump super PAC, America First Action, has been running millions of dollars in ads supporting Trump and attacking Biden. Among major donors to the super PAC in 2020 were Trump’s longtime friend and major GOP financier Stephen Schwarzman, the chief executive of private-equity firm Blackstone Group ($3 million); Trump friend and real estate developer Geoffrey Palmer ($2 million); and investment banker Warren Stephens ($1 million).