This was someone elected to represent the lower class of roman citizens?

senator...
There was no specific official chosen to represent the upper class of Roman citizens. All the elected officials were supposed to represent all ranks of citizens equally, or at least give the appearance of doing so. If he did not, he would never get elected to any other office. However there was a pair of aediles, called the curule aediles who were chosen from the patrician class. They were the ones who were in charge of the public games, e Ludi Romani and the Megalerses.