(AP) — A super PAC formed to support Cory Booker’s Democratic presidential campaign is shutting down.

The group’s founder, San Francisco lawyer Steve Phillips, indicated in a news release Wednesday that Dream United had struggled to raise money. Booker, a New Jersey senator, has publicly disavowed support from super PACs, which aren’t required to disclose their donors publicly.

Phillips, a former college classmate of Booker’s, said that it became clear while trying to fundraise for Dream United “that the donor community is strictly adhering to Senator Booker’s publicly articulated wishes that he does not welcome independent support.” The group raised a little over $1.1 million during the first six months of the year, far short of Phillips’ stated $10 million goal.