Citizens United, a conservative outside group, is running $250,000 of advertising in Iowa promoting a Ronald Reagan documentary featuring former House Speaker Newt Gingrich, The Hill has confirmed.

The ad will run Thursday and Friday and then be back up after Christmas for a week, according to a group spokesman.

Gingrich has worked with the group on multiple projects and is close to its head, David Bossie. But group spokesman Jeff Marschner denied that they were running the ad to help Gingrich's presidential campaign, and insisted the move was just business. "It's for movie sales — Iowans are tuned in right now," he said, and pointed out the group ran a similar ad in August with Michele Bachmann around the time of the Iowa straw poll.

Gingrich has been bombarded with negative ads in Iowa and has not responded in kind, causing his poll numbers to nosedive in the state. Any positive spots featuring him are likely to help, and the ad reinforces a connection Gingrich has stressed between himself and Reagan.

Politico first reported the ad buy. Watch it here: