The top super PAC backing President Obama has topped its Romney-supporting counterpart for the first time ever in fundraising.

Priorities USA Action raised $10.1 million in August, according to disclosures filed Thursday with the Federal Election Commission. The group announced its total to reporters on Sept. 4, claiming its best monthly haul to date.

The pro-Romney super PAC Restore Our Future raised $7 million in the same month, according to its own FEC disclosures.

August marked the first time Priorities out-raised Restore in any FEC filing period, including every month of 2012 and the first and second halves of 2011. The closest it came was within $96k in May. Aside from that month, Restore has dominated: In June, for instance, Restore raised $20.7 million while Priorities raised $6.6 million.

A fundraising edge for Priorities would be significant, given that Republicans have dominated the outside-money race throughout 2012. Last year, Priorities got off to a slow start as Obama's categorical criticism of super PACs sent mixed messages to Democratic donors. In 2011, Priorities USA Action raised $4.3 million, while Restore Our Future raised $30.1 million.

Priorities USA Action has a more secretive sister 501(c)4 group, Priorities USA, which does not disclose its fundraising totals to the Federal Election Commission, making it impossible to know how much money the Priorities operation raised in August combined.

It should be noted that big donors have more super PAC options than these two. The GOP money machine American Crossroads, for instance, out-raised the Democratic down-ballot super PACs Majority PAC and House Majority PAC significantly in July-$7.1 million to a combined $3.2 million. The latter group has upped its fundraising dramatically to $5.6 million in August, signifying an uptick for Democrats.

But the August advantage for Obama's top super-PAC provides a feel-good moment for the president's supporters, signifying a greater appetite among wealthy Democratic donors.