Justin Bieber and Old Spice Campaign hot on YouTube

 In one of the largest viral video ad campaign ever launched, Old Spice is swarming YouTube.

The Procter & Gamble Co. brand released more than 180 videos featuring the campaign’s star, ex-football player Isaiah Mustafa (moo-STAH’-fah). In the videos, he responds personally to online queries or comments from various Web users and some famous ones, including Ellen DeGeneres and Alyssa Milano.

The videos, all of which feature Mustafa in a towel speaking directly to the camera, have been steadily released over the last few days. On Friday, they accounted for eight of the most popular 11 videos on YouTube and more than 21 million views in total.

The “Smell Like a Man” ad campaign was launched earlier this year by Portland, Ore.-based ad agency Wieden+Kennedy. The television spots have been popular and the first TV spot won a Cannes advertising festival award.

Likewise, Justin Bieber’s music video for “Baby” has taken off on the Web and is the most-watched video ever on YouTube.

The 16-year-old pop star’s video passed Lady Gaga’s “Bad Romance” video to take the all-time lead. More than 246 million have watched Bieber’s video on the Google Inc.-owned website.

Bieber tweeted a thank you to “Beliebers” and said the video’s success was “crazy.” The singer wrote: “I started on youtube so ... WOW!”

Bieber’s video and Lady Gaga’s switched positions briefly Friday, but as of late afternoon, Bieber was ahead by more than 600,000 views.

The most-watched clip on YouTube that isn’t a music video is the popular “Charlie bit my finger” viral video, which more than 210 million have watched.