(CNN) – Democrats are doubling down on their efforts to portray the GOP as beneficiaries of shadowy campaign finance schemes, launching a national television ad Wednesday accusing Republicans of maliciously shielding their largest corporate donors in a cloak of anonymity.
"You've seen the ads. Millions being spent by right wing groups to buy an election," the new ad from the Democratic National Committee says. "All from secret donors. What's not a secret is why. Republicans and their corporate buddies want to be back in charge."
It's a message President Obama and Vice President Biden have themselves hammered on the campaign trail and one that has stemmed primarily from the workings of outside groups such as the Karl Rove-backed organization American Crossroads and its affiliate, Crossroads GPS.
Because it is established as a non-profit "social welfare" organization under the United States tax code, Crossroads GPS is not required to disclose its donors - a provision that has led the group to raise and spend millions at a record clip.
Democrats and watchdog groups have accused Crossroads of bending campaign finance laws by structuring itself as a "social welfare" non-profit while running ads that clearly benefit the Republican Party. Crossroads has responded that their ads are permissible because they address issues, not candidates explicitly.
"Wall Street writing its own rules again," the DNC's new ad also states. "Big oil and insurance companies calling the shots. More jobs shipped overseas. Millions in attack ads to put the corporate interests back in charge."
The new ad, which will run on national cable at least through the end of this week, is the second for Democrats to take aim at campaign spending practices, an issue that often does not resonate with voters, most of whom are much less interested in campaign machinations then traditional kitchen table issues.
In an ad released two weeks ago, the DNC alleged groups like American Crossroads are "stealing our Democracy." Rove later called the attacks "baseless."