How do I gain respect from coworkers/people in general, without shedding my ability to joke around?

I am naturally someone who enjoys making jokes, being sarcastic, as well as being the type of person who tries to be supportive and thoughtful, doing my best to help others who are in need. I like who I am. I know I am a good person, and I get along with pretty much everyone. The problem is, I am often cast into the nice guy category and am not taken seriously by coworkers due to my naturally empathetic nature.

There are certain individuals who are respectful and nice and nonjudgmental towards me one on one, joking around with me and not being aggressive or anything like that, but whenever another coworker comes around, they will start to talk to me negatively or try to make me seem like less than them, suggesting that I am inferior, but it is hidden behind a joking demeanor. An example would be, if we were discussing a method of performing a task at work, and then a coworker happened to walk up, the person would then become more verbally aggressive and try to establish dominance and superiority by saying something such as "Just shut up and get back to cleaning" in a slightly joking manner while still maintaining a somewhat seriousness to the statement. The message is there, but it's beneath this attitude where if I were to either react as though it hurts to be spoken to like that, I am being too sensitive and am overreacting and they will say "shut up you know I'm just joking, don't be such a b***h", and if I react by confidently confronting them and saying "I don't appreciate being spoken to in such a manner" I come off as being too serious and taking things personally. Then, if I do nothing and just laugh or brush it off, it teaches others that I am okay with being spoken down to and that I do not deserve respect. No matter what I do, I lose.

I've tried speaking to these people about it privately, hoping to diffuse the tension of them trying to establish dominance over me in front of others, and that goes well, but then in a situation where they revert back to previous behavior, they will either act oblivious to what they are doing, and later say they didn't know they were doing it, or they will stop and sarcastically say "Oh yeah sorry I don't wanna start acting all superior on you.." essentially blowing me off and making me look stupid in front of other people.

How do I stand up to them without going through the awkward conversations of saying it hurts me, or trying to be all serious and assertive since that isn't how I want to have to behave. I just want to be equal and demand the respect that I give to them, and I don't want to have to stop joking around and being nice to people. I want to be able to be taken somewhat seriously without being taken too seriously.

Sorry for the lengthy post, but I've thought about this a lot. Any help would be greatly appreciated.

Thank you