The ad, titled "Facts," was launched by the Democratic Senatorial Campaign Committee last week and claims to outline Berg's ties to Goldmark Property Management, which violated fire codes and has received numerous tenant complaints.

But the ad came under scrutiny from the Berg campaign, which called for it to be taken down Friday, saying it was inaccurate.

A number of stations, including KFYR in Bismarck and Valley News Live in Fargo and Grand Forks, took the ad off the air on Monday. Jim Wareham, president and general manager of Valley News Live, said the ad was taken down due to legal concerns raised by the station's attorney.

Though he wouldn't detail the concerns specifically, they seem to center around the original ad's claim that Goldmark Property Management "was even listed as Berg’s employer on his real estate license and on federal forms."

The Democratic Senatorial Campaign Committee has released a revised ad that offers essentially the same evidence as the first, but with that line tweaked. The new ad says instead that GPM "was even on Berg's real estate license and was listed as his employer on federal forms."

The real estate license in question does not explicitly list GPM as Berg's employer; it simply says that Berg is "associated with" the company.

Berg's relationship to the Goldmark family of companies has become a central focus of Democrats in the state hoping to boost Democrat Heidi HeitkampMary (Heidi) Kathryn HeitkampSenate rejects Trump immigration plan Cramer to announce North Dakota Senate run on Friday Senate Democrats not sold on bipartisan immigration deal MORE's chances at a win. With the most recent poll — and only the fourth independent poll of the race out thus far — putting them neck and neck, with 47 percent support each, the race could come down to personal issues like this one rather than larger policy-focused debates.

Watch the revised ad: