The Government Integrity Fund Action Network, a Columbus, Ohio-based super PAC that dropped a late $1.1 million ad buy opposing Connecticut House candidate Elizabeth Esty last week, disclosed today the big donors who funded it: A pair of political nonprofits that don't disclose their donors.

New Models LLC contributed $627,000, while the Government Integrity Fund, a nonprofit sister organization of the super PAC, gave $475,000. Because both New Models and the Government Integrity Fund are social welfare organizations, they are not required to disclose their donors.

The three groups show why, in the post-Citizens United world ...