Iota Nada Nup Nothing

Ok friends, I need some help. I went to a friend's impromtu party on Saturday where low and behold, one of the partygoers is this guy that's asked me out 2 or 3 times in the past to which I've declined every time. And par for the course, he's trying again. Here's the tough part. I think this guy's somewhat attractive but we have NOTHING in common in the least. NOTHING. Did I mention there's not one drop of iota nada nup nothing that we have in common? Well, there isn't. Which is why I've declined 2 or 3 times now. However, you have to give this guy kudos for being persistent. I mean, c'mon, if a guy tells me "no" even once, I'm not going back in the ring for another round of rejection. Hell no, if I'm down, I'm down for the count. But for whatever reason, this guy, like one of those new foam core mattresses that retains it's shape, keeps coming back. And maybe his persistence is paying off, because I feel like I might cave. He may have made some progress. Which is where all of you come in. I need some advice. Do I keep saying no knowing that there's really nothing we'll connect on, or do I keep an open mind and finally say yes to this poor guy to just see what happens? If I'm going to be totally honest, I've said no in the past because I felt like he'd be the type to fall in love quickly. You know the kind. The ones that think you're the "one" after just one date. He's already told me I'm the "marrying kind." I'm the type that holds my heart back, and I fee like I'd be in the predicament of breaking a heart. That is usually the case when it comes to men for me. Sometimes it's so much easier in the beginning to say no, then to actually say yes only to say no after someones feelings are involved. Did that make any kind of sense? I have to admit, I enjoy the attention, but in the few mutual parties we've been at together, there just hasn't been anything of interest that we'll both agree to enjoying. For instance, he's a big video-gamer and I'm sooo not. If it were up to me, I'd go back to old school nintendo with only the up/down/left/right and A/B buttons. Believe you me, I can kick some Super Mario Bros. fire-ball breathing dragon ass to save the princess! Better yet, the Atari joy stick. I could at least manage that in getting Frogger through the traffic. But these days, my goodness, I can't make my fingers (yes, all 10 of them) figure out which buttons to push when! Another for instance is that he doesn't really watch football, and we all know what a HUGE fan of football I am. It consumes my life in the Fall. I know those are superficial things, but those are just 2 of many. So guys, what do I do? Do I stay the course and say no again? Do I say yes to prove to myself and to him that I was right in saying no all of this time? Or do I say yes and maybe become pleasantly surprised that we actually may have something in common to talk about? I know I'm making this a lot more complicated then it should be, but I've found myself in this same situation more times then I can shake a stick at, and I've never come home pleasantly surprised. Usually I'm telling the guy after a few boring dates that I don't think we should see each other anymore, only to be stalked by the guy, or to have him cry in my car for an hour, or to have him send me a cassette tape of songs that remind him of me. With those experiences in my past, I thought I had learned my lesson, but because this guy keeps coming back like the freakin' energizer bunny, no is getting harder and harder to tell him. Thoughts or advice anyone?