Acronym, which includes a hybrid model of a 501(c)4 entity that does not disclose donors and a Super PAC that does, has been a favorite for deep-pocketed Democratic donors. Donald Sussman, the founder of Paloma Partners, and Michael Moritz, a partner at Sequoia Capital, each donated $1 million to Acronym last year. Filmmaker Steven Spielberg gave $500,000. Investor Seth Klarman, once a major donor to Republican causes, gave $1.5 million to Acronym.