Post a new rule... "you must have showered recently and not smell like ass in order to play. if you don't want to shower, the casino is down the road"
i agree with that... theres this one kid that comes to my game sometimes straight from a baseball game... i usually dont let him play unless were shorthanded...
every town has that one stinky guy that needs to be everywhere. i have yet to find my town's stinky guy and i go anywhere i can to find him.
just flat out tell them they need to clean up. you are not offending someone by telling them. it's the other way around. they are offending other people. just try a more tactful way than just "take a shower you stinky bastard" which is what i use to tell people that stink. and i run into a lot of them driving a taxi. there are some regulars i won't let into my car until i get a whiff of them first (and these people are coming from home not work which i will let a working stiff stink).
don't offend people by letting this guy come to your game unless he cleans up. it's better to offend one than all. it's easier to replace one player than a room full.