Joe Biden's naming of Sen. Kamala Harris of California as his running mate triggered a fundraising surge.

The presumptive Democratic nominee’s campaign confirmed to Fox News on Thursday that they raised a massive $48 million in the 48 hours following the former vice president’s Tuesday announcement.

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At a virtual grassroots fundraiser with Harris a day earlier, the former vice president touted that in the past 24 hours "we raised $26 million."

Democratic presidential candidate former Vice President Joe Biden and his running mate Sen. Kamala Harris, D-Calif., participate in a virtual grassroots fundraiser at the Hotel DuPont in Wilmington, Del., Wednesday, Aug. 12, 2020. (AP Photo/Carolyn Kaster)

And he noted that 150,000 of the donors were first-time contributors to his presidential campaign.

"It's really palpable, the excitement," Biden said.

Harris helped Biden bring in campaign cash even before she was picked as the Democratic Party's vice presidential candidate. A fundraiser in early June headlined by the former vice president and the senator brought in nearly $4 million.

President Trump’s reelection campaign said last week that the campaign, the Republican National Committee (RNC) and its joint fundraising committees combined brought in an eye-popping $165 million in contributions in August. They also touted that they had more than $300 million cash on hand as of the end of July.

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The combined Trump campaign/RNC haul was a record and is up more than $30 million from the $131 million it raised in June. The war chest total appears to be a slight increase from the $295 million they had in their campaign coffers at the end of June. The campaign spotlighted that July was their largest online fundraising month ever.

The announcement from Trump’s reelection team came a couple hours after Biden’s presidential campaign reported that it, the Democratic National Committee (DNC) and its joint fundraising committees combined hauled in $140 million last month.

The former vice president’s campaign also touted that they have a $294 million in cash on hand as of the end of July, an increase of $50 million in their coffers over the past month.

The $140 million brought in during July is roughly equal to the $141 million the Biden campaign and the DNC raised in June, which was by far the campaign’s best monthly figure to date.

The president’s been raising money for his reelection bid since entering the White House three-and-a-half years ago. And the reelection effort’s hauled in an unprecedented $1.1 billion the past two years.

The former vice president, who declared his candidacy in April of last year, struggled to bring in cash for much of his campaign. He raised just $8.9 million in January and $18 million in February. But he saw his fundraising spike starting in March, as he became the clear front-runner for the Democratic nomination and much of the party coalesced around his White House bid. Biden became the presumptive Democratic presidential nominee in April, as his last remaining primary rival – Sen. Bernie Sanders of Vermont – dropped out of the race and backed the former vice president.

The Biden campaign surge in fundraising the past couple of months – it narrowly outraised the Trump campaign in May and June – helped it trim the president’s once-massive cash-on-hand advantage.

Reuters first reported the $48 million figure.