Herman Cain says ad not meant to push smoking

(CBS) Herman Cain said Sunday that a campaign video featuring his campaign manager smoking wasn't intended to promote tobacco use.

PICTURES - Teen smoking: 25 deadliest states 

The ad went viral this month with some 1 million clicks on Cain's campaign website, AP reported. shows Cain adviser Mark Block taking a deep drag from a cigarette and slowly exhaling into the camera.

"We weren't trying to say it's cool to smoke," Cain said on CBS' "Face the Nation." "You have a lot of people in this country that smoke. But what I respect about Mark as a smoker, who is my chief of staff, he never smokes around me or smokes around anyone else. He goes outside."

Could the ad actually deter smoking? One antismoking expert thinks it might.

"This guy doesn't look very cool to me," Dr. Ruth Malone, professor and chair of the department of social & behavioral sciences at the University of California at San Francisco, said of Block in an email to CBS News. "In fact, he looks like he could keel over from a heart attack any time - so if anything, it may make smoking appear less cool."

When "Face the Nation" host Bob Schieffer asked Cain to send an anti-smoking message on the show, he complied.

"Young people of America, all people, do not smoke," the Republican hopeful said. "It is hazardous and it is dangerous to your health. Don't smoke. I've never smoked and I have encouraged people not to smoke. Smoking is not a cool thing to do."

Cain was diagnosed with liver and colon cancer in 2006 and has said he's been cancer-free since 2007, according to AP.

Smoking is the #1 cause of preventable death in the U.S., claiming more than 440,000 lives each year.

The American Cancer Society has more on smoking and cancer.