Can I sue someone in small claims with no contract or signature?

[teyo]

If I bailed a friend out of jail for $750 but did not make him sign a contract that he would pay me back, except for a personal promise in words, then can I still try and sue him in court?

[gervaso81]

Sure

It'll be nearly impossible to win. Can you at least prove that you did loan him the money? Do you at least have a witness to testify this was't just a gift?