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Ratings for “Two and a Half Men” are falling in the wake of Ashton Kutcher’s alleged affair with a 22-year old party girl. Viewership has fallen week-to-week since the actor took over for Charlie Sheen, during which time tabloid headlines have been full of Kutcher’s reported one-night-stand with a young blonde on his and wife Demi Moore’s sixth wedding anniversary.

After the show debuted on September 19, the ratings fell off from 28.7 million to 20.5 million, a 28 percent drop. The next week the audience fell to 17.5 million, then to 16.2 million. This week’s episode lost another six percent, down to 15.1 million.

Some experts say Kutcher’s brand may be permanently damaged from the tabloid scandal, and that could cause some women, who may have flocked to Team Kutcher because of his seeming fidelity to his older wife (Kutcher is 33, Moore is 48), to lose interest in the actor and his show.

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“Ashton’s brand is definitely tarnished. Unlike Charlie Sheen, he didn’t have a wild bad boy persona. His brand was built up as a loving husband to Demi Moore and a great step dad to her kids,” Bonnie Fuller, Editor in Chief and President of Hollywood Life tells Fox411. “Women were so impressed with that, and that is why they liked and supported him.”

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This is reflected in Kutcher’s character on the show. Kutcher plays an adorably doofy Internet billionaire who is lost in love after his wife leaves him.

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“There is nothing adorable about having a one night stand with a party girl,” Fuller continued. “If the allegations are true, then Ashton looks like just another sleazy Hollywood man.”

But the added attention on Kutcher may not be all bad, says media analyst Brad Adgate of Horizon Media.

“The show naturally had a curiousity factor right off the bat which is why we see the initial decline but the overall average audience is up 47 percent and in the 18-49 range it is up 59 percent compared to this time last year. The median viewer age dropped from 50.5 to 40.1. I think CBS still needs to be ecstatic,” Adgate told Fox411. “He is a younger actor and he is bringing in younger viewers to some extent. For a network like CBS, whose viewers tend to be older, this is something they have to be pretty pleased with.”

Adgate thinks all of the press for Kutcher, even the bad stuff, may actually be good for the show.

“A little press is better than no press. For years since he got married to Demi Moore, there wasn’t a lot of press surrounding Ashton. Now he is front and center again. It’s quite the coincidence, and maybe it will be good,” Adgate said.

TVLine.com editor Michael Ausiello agrees.

“During the peak of Charlie Sheen’s public meltdown last Spring, ‘Two and a Half Men’s’ ratings actually increased. The show is scandal proof,” Ausiello tells Fox411.

Regardless of the tabloid effect, Kutcher’s acting on the show has been roundly criticized. Of the premiere, The Wall Street Journal wrote “Kutcher is intense and doesn’t do deadpan well at all.” The New York Daily News added that Kutcher "needs to work on being funny.”

Tabloid scandals or not, at the end of the day, whether Kutcher’s stint on “Two and a Half Men” is a success or failure will depend on whether he is successful filling Charlie Sheen’s very large shoes.

"I think the key question is do the ratings continue to slide?” says critic Robin Pierson of TheTVCritic.org. “If next week the numbers drop further that would strongly suggest that fans of the show don't feel it's as enjoyable without Sheen involved. If the numbers remain steady then I think CBS will feel satisfied that losing Charlie won't have changed things at all.”