Even asking nicely wouldn't do it for me. I hate how smokers are demonised and can't do right for doing wrong. And the smokers I know are all like me and pretty unlikely to blow smoke deliberately in anyones immediate vicinity. Therefore I would consider this sort of request as seriously as I consider someone who develops a cough at a bus stop when I light a cigarette, am standing several feet away from them and we're waiting at a busy main road!
Sorry ladybirder, we'll have to agree to disagree on this. Until they make it illegal to smoke anywhere but your own home then outside is fair game to me.