As the old saying goes, "I only know what I read in the paper" -- in this case, the on-line edition. The brief story lacked details on the poll's methodologies. But I share your skepticism, and that of Gabz and others, based on the small sample size. Then, there's the tendency, when polled, to provide a "politically correct" answer, which lately means anti-smoking. So I do suspect that the percentage who would favor a ban may be inflated. That said, anecdotal evidence (which is to say, my observations of bars and restaurants) convinces me that the percentage of smokers is falling fast.
As previously noted, I oppose government smoking bans. Mainly because the problem (if you regard it as such) will solve itself. In Charlotte, the number of restaurants/bars which have gone smoke-free is rapidly increasing -- lots of fast-food places, as part of the national policies of the chains, but of more interest to me, more and more upscale places. This is particularly true of new establishments. I try to patronize smoke-free places myself, but I don't obsess over it. If a smoke-friendly establishment has the best steak in town, I'm there. A well-ventilated bar (especially given that fewer and fewer people are smoking these days) and a table in the non-smoking section is all the "protection" I need.
But it's a moot point, in my judgment. Smoking will be all but gone from bars and restaurants, from sea to shining sea, in a very few years, certainly less than five. The reason will be litigation purporting to protect restaurant employees. If second-hand smoke is deemed to be harmful to office workers and flight attendants (it isn't, or only very slightly so, in my opinion), then lawyers representing food service workers will make the same claim. And they'll succeed.