Priorities USA Action, the super PAC supporting Obama, raised $4 million in May, according to its FEC report released today. This marks the group's best fundraising month since it began, and a big improvement from April, when they raised just $1.6 million.

The group reported spending $4.2 million in May, and ended the reporting period with $4.5 million cash on hand. They report owing no debt.

Priorities' total raised for the month was not that far behind the pro-Romney Super PAC Restore Our Future, which has so far surpassed the Democratic group in its fundraising. Restore Our Future reported raising roughly $5 million in May. The group still holds a sizable cash-on-hand advantage; it reported ending the month with $8.4 million in cash.

There were no celebrity donors to Priorities this month (past donors have included Bill Maher and Jeffrey Katzenberg) but there were a few million-dollar donors: a retired woman named Barbara Stiefel in Coral Gables, Fla; Franklin Haney, CEO of FLH Company, a real estate development company in Washington, D.C.; and Steve Mostyn, an attorney in Houston.