Has President Obama taken his last puff?

>>> first lady michelle obama is marking the first anniversary of her drive to get america's kids to eat healthy and exercise. on this day there was a surprise revelation about one of the president's health habits. chuck todd with more on this tonight.

>> reporter: the topic of the president's smoking has always made the white house uncomfortable, and the president himself squirm a bit uncomfortably. it's been a nagging question since his election.

>> have you stopped smoking?

>> how many cigarettes a day do you smoke alone or in the presence of other people?

>> reporter: neither the president nor his staff have enjoyed answer the question.

>> i don't see the need to get a lot more specific than to say it's a continuing struggle.

>> you just think it's neat to ask me about my smoking.

>> reporter: the standard answer has been, he's almost an ex-smoker, but not yet.

>> i don't do it in front of my family, and -- i would say that i am 95% cured.

>> reporter: it's a washington parlor game, where does he do it? on the white house grounds? the truman balcony, perhaps? or more likely the golf course ? the president's most frequent golfing companion is aide marvin nicholson who has also struggled with smoking. after the president's last physical, his doctor recommended he continued smoking cessation efforts.

>> the president continues to chew nicotine gum.

>> reporter: and apparently it's worked. first lady michelle obama told reporters the president hasn't smoked in a year. but it hasn't been easy. nobody has been more critical than mrs. obama. here she is on "60 minutes" way back in 2007 .

>> please, america, watch. keep an eye on him and call me if you see him smoking.

>> reporter: the president who first started smoking as a teenager, brian, clearly has been embarrassed by this habit. he hated to talk about it in off the record settings. but what helped this time according to robert gibbs is that close aides and a couple others have also quit with him. they've all been smoke free for a year.

>> power in numbers. i guess the last dedicated smoker in the white house was fdr. it's been a long time. chuck todd , thanks.