A mystery donor has given the biggest donation so far to Luigi Mangione’s defense fund, inspired by the “quite exceptional” support for the man suspected of gunning down UnitedHealthcare CEO Brian Thompson.

The “anonymous giver” gave a staggering $36,500 earlier this week — topping the previous record of $30,000 as the total exploded to over $722,000.

The nameless benefactor said he or she was inspired by the huge swelling of support from a wide cross-section of people for the 26-year-old UPenn graduate charged with the shocking murder outside a Manhattan hotel in December.

“What intrigues me about this case is how unified folks’ responses are regardless of strata,” the benefactor wrote.

“In Corporate America, for instance, there has been widespread doubt of potential prosecutorial mishandling and overcharging.

“I’ve also been surprised at the almost ubiquitous nature of support towards the suspect that I would expect to be quite bifurcated in this type of litigation. Quite exceptional,” they added.

The new donation eclipses the former top donation by $6,500.

Mangione is being held without bail in a Brooklyn federal lockup where he’s received incredible support in the form of letters from fans while in jail, many including photos of his throngs of female supporters.

The alleged murderer’s defense fund swelled after he was rumored to be in a number of sex tapes circulating online.

His attorney Karen Agnifilo told the Daily Mail the videos are “fake and not Luigi.”

The fund was launched on Dec. 9 after Mangione was arrested at a Pennsylvania McDonald’s following a frantic five-day manhunt on the heels of Thompson’s murder in Midtown.

Mangione could face the death penalty if convicted at his federal trial on charges related to terrorism in the case.