I voted no, but I feel like the poll was too absolute with only two options to give me an accurate way to vote, so I have to explain how I actually feel about it.
Generally speaking, fitness level is something I'm really attracted to. Not like, the works-out-two-hours-in-the-gym-every-day guy, but just the guy that gets regular exercise, eats right, and stays pretty trim. It would determine a lot of what we would do together- play sports, go hiking, go cycling, things like that, and it shows where they put their priorities (assuming they have no medical condition otherwise). I'm kind of a health nut when it comes to what I cook and what I do, so it seems like there would be a lot of incompatibility there if I tried dating someone that wasn't into much of that stuff. In practice, if I recall all of the guys I've been attracted to, they were generally not overweight people.
But, it depends how overweight we're talking. There are a range of healthy body shapes. To me, it's not like I'm going to measure their body fat percentage and see if it's over some cut-off point. Instead, what would attract or not attract me to them are behavioral things, like how disciplined their personality is, what their activities tend to be, what their food habits tend to be, what sort of style they have, and how they take care of their body, and most of that happens at a subconscious level for me. So it's not as simple as a "yes" or "no" question for me.