Updated

A political TV ad targeting a black candidate for Senate contains what critics, including the NAACP, are calling racist sexual innuendo about a black man and white woman.

The Republican National Committee ad began airing Friday and features a series of characters facetiously declaring their support for Democrat Harold Ford Jr., a Memphis congressman who faces Republican Bob Corker, who is white, in the Nov. 7 election. Polls have shown the two locked in a tight race.

In the ad, a blond white woman brags, "I met Harold at the Playboy party." At the end she looks into the camera, holds her hand like a telephone and says, "Harold, call me," before winking.

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The line is an apparent reference to Ford's attendance at a Playboy Super Bowl party in Jacksonville, Fla., last year.

"I was there. I like football, and I like girls," Ford said Tuesday.

"I don't think they're doing it to talk about the goodness of me or the goodness of my opponent," Ford said. "They want to scare people about me."

The National Association for the Advancement of Colored People criticized the ad.

"It is a powerful innuendo that plays to pre-existing prejudices about African-American men and white women," Hilary Shelton, head of the Washington NAACP office, told the Los Angeles Times.

The Corker campaign denounced the ad, saying it is "tacky, over the top and is not reflective of the kind of campaign we are running."

RNC spokesman Danny Diaz has defended the ad's accuracy and said it will run its full course. It cost $457,944 to buy the time for the ad, according to Federal Election Commission filings.

Because the ad was created by an outside group that contracts with the Republican National Committee, neither the RNC nor Corker's campaign saw it in advance and can't order it to be taken off the air.

Under the Bipartisan Campaign Reform Act passed by Congress in 2002, political parties can pay for "independent expenditure" advertisements against opponents that do not count against legal spending limits on campaigns. But the party is not allowed to play any role in creating the ad or deciding how and when it will be used.

Former Clinton Defense Secretary William S. Cohen, also a former Republican senator from Maine, said on a cable news network that the ad was "a very serious appeal to a racist sentiment."