Typically you have to refer to the state statutes and how a lottery and charitable gaming are defined. It comes down what consideration is offered for the bet. Generally, a 50/50 lottery complies with the statute because there is no consideration offered. But betting on the individuals is probably illegal. This is similar to a race or sports betting, which is highly regulated if it is legal in your state.
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Doubtful, but check with the proper agency that regulates betting, games of chance, etc., in your state. In some jurisdictions that is the Attorney General's office. I see in PA there is a Gaming Control Board, so you could start with them:
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