Yes, I agree with this statement. A good politician needs to get the people on his side in order to gain popularity and power. Because Antony is such a persuasive speaker, he is highly successful at drumming up support for his cause. Originally, this cause is presumed to be revenge for his slain friend Julius Caesar. However, during Act 4 we learn about the true Antony, and that Caesar's assassination was actually his opportunity to crawl out from under Caesar's shadow and a chance at a power grab. This is best evidenced in Act 4, Scene I when he makes changes to Caesar's will so that he can get more of the inheritance. He also shows he's morally unjust in the same scene when he secretly plots to remove Lepidus from the triumvirate.
On the surface, Antony looks like the noblest of all Romans, but underneathe he is more ambitious and deceitful than any man in Rome. This is the sketching of a true politician.