 -- The Republican advocacy group Crossroads GPS unveiled a $7 million-television ad buy Tuesday to air a commercial criticizing President Obama for increasing the national debt during his presidency.

"In the seconds it takes to watch this, our national debt will increase $1.4 million," the narrator says as a clock ticks away on the screen, and accuses Obama of "adding $4 billion in debt every day, borrowing from China for his spending."

The 30-second spot will run in markets throughout swing states Colorado, Florida, Iowa, Michigan, New Hampshire, Nevada, North Carolina, Ohio, Pennsylvania and Virginia over the next two weeks.

The organization behind the ad is a sister group to American Crossroads, a super PAC co-founded by Karl Rove, a former aide to President George W. Bush. Because it is legally organized as a non-profit, unlike super PACs, it is not required to reveal its donors.