Former President Trump is on track to raise $43 million at a fundraiser in Palm Beach on Saturday, in what many billionaire Republican donors are considering the kickoff for the general election, sources tell Axios.

Why it matters: That haul would eclipse the $26 million raised by President Biden last week at his celebrity-studded Radio City Music Hall event, which was billed as the largest fundraiser in political history.

Trump's "Inaugural Leadership Dinner," led by hedge-fund billionaire John Paulson, tops out at a "Chairman level" of $824,600, which includes "dinner seating at President Trump's table."

• The event will feature former first lady Melania Trump and three of Trump's former primary opponents — Sen. Tim Scott (R-S.C.), Vivek Ramaswamy and North Dakota Gov. Doug Burgum.
• A source familiar with the event planning tells Axios: "This event is greatly exceeding expectations and shows the Republican Party is united behind President Trump."

How it works: Sources tell us the eye-popping total was achieved with personal phone calls by Trump, "peer-to-peer asks" (in this case, some literal billionaire-to-billionaire conversations) and a persuasive deck about the electoral outlook by campaign co-manager Susie Wiles.

The other side: A source involved in Biden's fundraising operation was skeptical of the total being touted for Saturday's event, saying that "getting everyone to max out in April" is "not a sustainable way to fund a campaign."

• "It's a recipe for being broke in the months that will matter," the Democrat told Axios.
• The source points out that under the joint Trump fundraising agreement outlined on the Palm Beach invitation, a swath of the event's proceeds will go to Trump's political PAC, which has been used to pay his legal bills. The agreement prioritizes the PAC over the RNC.