Of all male characters, Cinna and Haymitch are my favourites, but between Gale and Peeta, I'll stay with Peeta. Not because of his love-dovey-I'm-so-cute personality, but actually because I view him as being the stronger of all three (Gale, Peeta and Katniss); ok, Gale and Katniss have fire and combativeness, but Peeta has a balanced mind that makes him able to surpass anything without losing his sanity and self-understatement (EVEN losing his sanity and self-understatement). He knows who he is, and he knows what he wants (unlike Katniss, who always seems to be struggling with herself - not that it is her fault, it just is). I really think that if Katniss or Gale were hijacked instead of Peeta, they wouldn't be able to come out of it as good and Peeta did (except if Suzanne Collins decided to Mary-Sue their personality instantly, which she is kinda fond of doying, but anyway...). As Katniss herself said, Peeta is the only one able to give her stability.
Ok, sorry for the long text (and bad english). I already wreaked everything, I promise.
I'm pretty torn on this debate. I kind of like Gale more to be honest, because while Peeta is really sweet and I really love him at times, he can be a bit boring. I always felt that Gale and Katniss were perfect for each other and had a lot of chemistry, while I only felt a rather forced love between Peeta and Katniss. I hated Gale in the last book though Suzanne Collins made him seem like a die-hard war freak or something. So yah, I could also say I prefer Peeta, I guess I just don't know!