In the sentence presented "We have spent millions of dollars on commercials. I think it will be easy to convert the audience to our party’s beliefs" the word "convert" is used to as a synonym of convincing or changing to refer how easy the speaker believes the audience will change its ideas or beliefs due to the commercials. This implies, in this case, the word "convert" mainly means "to turn toward" rather than to carry away, argue over or leave behind as this word implies a change of perspective and beliefs.
I think this because this sentence is only the sentence that goes along with the passage. The passage talks about the features of the penguin, not anything else about it.