Two days before Christmas, a trust called DE First Holdings was quietly formed in Delaware, where corporations are required to reveal little about their workings. A day later, the entity dropped $1 million into a super PAC with ties to Jersey City, N.J., Mayor Steven Fulop, a Democrat considering a gubernatorial bid.

The trust, whose owner remains unknown, is part of a growing cadre of mystery outfits financing big-money super PACs. Many were formed just days or weeks before making six- or ­seven-figure contributions — an arrangement that election law experts say violates a long-standing federal ban on straw donors. But the individuals behind the “ghost corporations” appear to face little risk of reprisal from a deeply polarized Federal Election Commission, which recently deadlocked on whether to even investigate such cases. READ MORE