The ad, running on Spanish language radio stations, calls the former first lady "shameless" and says she "does not respect our people." It also slams efforts by some Clinton backers to block special precinct caucuses on the Las Vegas Strip for casino workers.
Clinton used the same language to criticize the ad and Obama's indirect connection to it.
"They're shameless and offensive," Clinton said of the ads, noting that Obama had denounced commercials run by labor unions and other independent groups in Iowa that supported John Edwards.
"You would hope that Sen. Obama had the same standards in Nevada that he had in Iowa. Obviously we're calling on him to do that here," she said. "I think it's way beyond bounds for anyone to make the shameless and offensive claims that are in those ads."
The Obama campaign has said the Illinois senator does not encourage outside groups to advertise on behalf of individual candidates. But Obama has not distanced himself from the claims in the ad.
Clinton also said she was concerned that some Culinary Union members were being discouraged from caucusing for her, citing media and blog accounts of such complaints.
She also said her campaign office had received a flood of calls and e-mails suggesting such intimidation was taking place.
"The evidence is pretty compelling," Clinton said.
Clinton spoke to reporters during a final campaign swing throughout Nevada. She was making four stops across the state, ending Friday night at a Las Vegas rally with President Clinton.
