Whitman's $119 million in personal contributions to her campaign broke Bloomberg's previous record of personal spending on a single race.
The billionaire mayor spent $109 million of his own money on his re-election to a third term last year.
He said Thursday that her spending record shows she must care about California and believes she can improve it.
Bloomberg pointed out that other candidates spend the public's money.
He joked that Whitman probably didn't break his record per capita.