The conservative nonprofit group Americans for Prosperity (AFP), which is backed by the Koch Brothers, released an ad Wednesday attacking Sen. Mary Landrieu (D-La.) over her support for the Affordable Care Act. But as ABC News reported Thursday, the people appearing as Louisianans in the spot are paid actors.

In the ad, the actors open their mailboxes while a narrator describes letters from insurance companies saying their family's plans are no longer available, doctors are no longer in their network and their monthly premium has increased.

The Landrieu campaign hit back Thursday against the use of professional actors portraying the state's residents.

"Hiring professional actors to impersonate Louisiana families is low even for the billionaire Koch brothers, who are spending millions to distract voters from their campaign to kill bipartisan flood insurance reform, our state's top legislative priority with unanimous support from our Congressional delegation," the campaign said in a press release. "If the Koch brothers had even a shred of credibility before launching their latest misleading ad campaign against Sen. Landrieu, they've surely lost it now."

Americans for Prosperity spokesman Levi Russell told ABC News that the ad, which is scheduled to air for three weeks, is meant to be “representative of Americans from all walks of life.”

“I think the viewing public is savvy enough to distinguish between someone giving a personal story and something that is emblematic,” Russell said. “And we make it very clear when someone is giving a personal testimonial.”