Who is generally considered to be the main character of Shakespeare's play, Julius Caesar?

Though the play centers on the assassination of Julius Caesar, he is killed early in the play, and he himself is not the main character. Some experts have speculated that the play should be called "The Tragedy of Marcus Brutus", as Brutus, a close friend of Caesar and very loyal son of Rome, is the one with the internal conflict who chooses to slay his friend for what he believes to be the good of the Empire. The rest of the play concerns the battle among the conspirators and the heirs apparent to the control of Rome -- primarily between Antony and Brutus. The play ends with the death of Brutus and with his enemy, Antony, pronouncing that Brutus had been "the noblest Roman of them all."