>>can you smoke suckers ?>>
Yes indeedy...
When they were kids, my Dad and his brothers used to catch them out of Elk Creek when they were on their Spring spawning run and they'd smoke a bunch of them every year.
Have to get them when the water is fairly cold though, say under 50F. Otherwise, their flesh can be kind of mushy.
But that's axiomatic about suckers anyway, whether you are smoking them or cooking them by some other means.