Democrats accused advocacy groups allied with Republicans of "stealing our democracy" in a new national television ad released Sunday.

The Democratic Party upped its ante against the U.S. Chamber of Commerce and American Crossroads, a conservative advocacy group founded by prominent Republicans Karl Rove and Ed Gillespie, with the new ad.

"Karl Rove, Ed Gillespie: They're Bush cronies. The U.S. Chamber of Commerce: They're shills for big business," the Democratic National Committee (DNC) ad says. "And they're stealing our democracy."

The ad caps off a week of attacks led by President Obama against the Chamber and other political groups spending to help Republicans in Nov. 2's elections. Democrats complain that a Supreme Court ruling earlier this year freed up those groups to spend on the election without abandon, and without any disclosure of their donors.

In particular, Democrats complain that foreign-based individuals or corporations could funnel money through those groups to influence the election. The Chamber has vehemently denied using such practices, which would be illegal.

"It's incredible, Republicans benefiting from secret foreign money," the ad says. "Tell the Bush crowd and the Chamber of Commerce: Stop stealing our democracy."

The ad will run on national cable throughout the entirety of the coming week. The DNC effort also comes as Gillespie is set to appear on CBS's "Face the Nation" on Sunday. Rove is a regular contributor to Fox News. 

"The big question is whether Tim KaineTimothy (Tim) Michael KaineManchin on collision course with Warren, Sanders On The Money: Incomes, consumer spending soared in March | Harris, senators work behind scenes on jobs package | Biden cancels some border wall construction Harris, senators work behind scenes on jobs package MORE and Barack Obama, whose accusations about foreign money were eviscerated by the New York Times today, approved of this desperate, sophomoric and libelous advertisement," American Crossroads spokesman Jonathan Collegio said.

"The DNC ad is rubbish," said Tom Collamore, senior vice president of communications and strategy for the U.S. Chamber. "The U.S. Chamber will continue to discuss ways to create jobs and grow the economy no matter how often others may try to change the conversation. We’ve been working for growth, jobs, and opportunity for 100 years and we won’t be deterred now."