Democratic presidential candidate former Vice President Joe Biden walks to his car after visiting the Buttercup diner on March 03, 2020 in Oakland, California.

Former Vice President Joe Biden went into Super Tuesday with fewer financial resources than other candidates. But he will be in much better shape by the end of the night.

Bundlers loyal to Biden are seeing dozens of new donors, several maxing out with the top allowable $2,800, as he picks up victories in Virginia, North Carolina, Tennessee, Oklahoma, Alabama, and other states, according to people with direct knowledge of the matter. These people declined to be named because these developments were yet to be announced.

Biden fundraising events started to sell out early in the night, the people added.

Biden's fundraising success on Tuesday will be a key to his efforts to win the Democratic Party's nomination to take on President Donald Trump in November. Sen. Bernie Sanders, I-Vt., who was ahead of Biden in the delegate count going into Super Tuesday, raised $46.5 million in the month of February. Biden, meanwhile, raised $18 million over that same time period and another $5 million just days after his dominant victory in Saturday's South Carolina primary.

Former New York Mayor Mike Bloomberg, a billionaire worth about $60 billion, has said he will not be dropping out in the near future, making Biden's fundraising success on Tuesday even more critical.

Bloomberg invested $200 million in Super Tuesday ads, including $5.6 million in Virginia and $12.8 million in North Carolina. Biden's campaign spent just over $445,000 on ads in both of those states combined.

Business executives who were advising both Bloomberg and Biden have also started privately deciding to side with the former vice president. With Bloomberg appearing to struggle, these same business leaders and donors are planning to prod the former New York mayor to drop out of the race in order to become, in essence, another financial juggernaut that will back Biden and turn on Sanders.

"At some level it is shocking to win double digits in Virginia, for example, and with no ads and no ground game except a single field office," said one Wall Street leader who was helping both candidates but is now calling on members of his network to back Biden.

Jon Henes, a fundraiser for the former vice president, told members of his donor network that the message of Super Tuesday is clear: Biden is the candidate to beat, and it's time for Bloomberg to go.

"Mayor Bloomberg's attempt to bring a new approach — forgoing the first four states, plowing money into social media and advertisements and opening offices in the Super Tuesday states, did not work. It is definitely time for Mayor Bloomberg to step out and support Joe," he told donors late Tuesday.

One of the nearly sold-out events is at the home of former Ambassador James Costos, said the people with direct knowledge of the matter. The event is scheduled for March 19, two days after the Florida primary. It was described to CNBC as an LGBTQ reception that looks to appeal to donors who once backed former South Bend, Indiana, Mayor Pete Buttigieg before he dropped out earlier this week and endorsed Biden. Buttigieg was the first major openly gay presidential candidate.

The event is to be co-hosted by Wall Street executive Charles Myers, former Ambassador Rufus Gifford, and Rep. Sean Patrick Maloney, D-N.Y., among many others, an organizer explained. As Biden picked up a win in South Carolina, donors close to Buttigieg and Sen. Amy Klobuchar, D-Minn., who also recently dropped out and endorsed the former vice president, started moving into his camp.

One bundler explained to CNBC that Biden's Super Tuesday success is leading to potentially 30 events being scheduled across the country, with 15 already lined up.

"I have been inundated with requests to give and to hold fundraisers," Florida businessman John Morgan explained to CNBC. "The worm has turned. Uncle Joe is the new comeback kid."

Another Biden bundler, Mike Kempner, told CNBC that money is rolling in in the wake of the campaign's Super Tuesday success.

"Since South Carolina, there has been a steady stream of new donors wanting to be supportive. After tonight that is now a flood," said Kempner, CEO of public relations giant MWWPR. "The enthusiasm from new and current donors is at a level rarely seen in fundraising circles."

Meanwhile, the pro-Biden super PAC Unite the Country has also seen new big-money commitments throughout the evening. The group is looking to help Biden in future primaries after investing in digital and radio ads airing in key Super Tuesday states.

"We are riding the VP's coattails. The donors are making their preference known," Larry Rasky, the group's treasurer, told CNBC on Tuesday when asked about their success throughout the night.