The lawyer for President Obama demanded on Tuesday that Crossroads GPS disclose its donors, saying in a complaint to the Federal Election Commission that the group is plainly a “political committee” subject to federal reporting requirements.

In the complaint, obtained by The New York Times, Robert F. Bauer, the campaign’s chief counsel, writes that the group — founded by Karl Rove, among others — can no longer shield the identity of its donors by defining itself as a “social welfare” organization.

“Crossroads seems to believe that it can run out the clock and spend massive sums of money in this election without accounting for a trace of its funding,” Mr. Bauer wrote in the complaint, filed Tuesday. “Now, a federal appellate court has issued a ruling that makes clear that Crossroads is out of time.”