CNN

(CNN) – After nearly a month of Republican assaults on the fundraising of Sen. Barack Obama, the Democratic National Committee is returning fire.

The DNC announced Saturday that it intends to file a complaint with Federal Election Commission about contributions to Sen. John McCain’s presidential campaign.

Read: The DNC's FEC complaint

Democrats will ask the FEC to investigate whether the McCain campaign accepted contributions in excess of the legal limits, entirely failed to report contributions, and accepted anonymous contributions in amounts greater than $50. The DNC will also request a complete audit of all contributions to the McCain campaign.

McCain was a co-sponsor of a 2002 law that effectuated a major overhaul of federal campaign finance laws. The DNC emphasized McCain’s history of supporting campaign finance reform in announcing its complaint. "The McCain campaign's lack of disclosure and disregard for the law he helped write raises serious questions about John McCain's commitment to the openness and transparency the voters expect from their leaders," the DNC’s General Counsel Joe Sandler said in a statement.

The Democratic complaint comes after the Republican National Committee and the McCain campaign have spent much of October assailing the Obama campaign for questionable donations and for lack of adequate controls to comply with legal requirements in its phenomenally successfully fundraising efforts which has yielded many small donations collected over the Internet.

Citing press reports, the RNC filed an FEC complaint that seeks an investigation into donations to the Obama campaign and an audit of every contribution to Obama including those donations the law does not require the Obama camp to disclose because they are less than $200. Republicans have also recently sought to pressure Obama to disclose his small-dollar donations even without a legal requirement to do so.