06/20/2012 09:29 pm ET

Barack Obama Super PAC, Priorities USA Action, Has Record Month

WASHINGTON -- The super PAC supporting President Barack Obama's re-election campaign raised $4 million in May, by far its best month since forming in 2011.

The huge haul came mostly from four donations: three for $1 million each and one for $500,000. The $1 million donors were Houston-based attorney Steve Mostyn, real estate magnate Franklin Haney, and Barbara Stiefel of Coral Gables, Fla. Perennial Strategy Group, a Washington, D.C.-based firm headed by Lamell McMorris that offers everything from government relations to sports agents, contributed $500,000.

Priorities USA Action, headed by former White House official Bill Burton, has had a rocky time raising money. The group has pulled in a total of $14.6 million. That places it in the top tier among super PACs, but pales compared with the $61 million raised by Restore Our Future, the super PAC backing Mitt Romney's campaign.

Recently, Priorities USA Action hired Mary Beth Cahill, the former campaign manager for Sen. John Kerry's 2004 presidential campaign, to help with strategy and fundraising. Cahill has also previously worked for the United Auto Workers and was the executive director of Emily's List, both connected to strong donor communities.

The pro-Obama super PAC's big fundraising month helped it spend big. The group spent $4.2 million in May, slightly less than Restore Our Future, which spent $4.7 million. The vast majority of Priorities USA Action's spending, $3.9 million, was on independent expenditures targeting Romney and supporting Obama.