Can a character study work if the main character isn't very likeable?

Like you may not particularily want to root for him. he is controversial and he may have a couple screws missin. if this person existed in real life you may not want to spend much time with him from fear of association. but through his journey i feel an important message is conveyed. its a screenplay by the way. and for the whole movie your pretty much stuck with him the whole way through. you think it can it work? thx