Re: Captain America... Spoilers
I'm not sure I'd actually put Cap on that list.
Cap is definitely iconic; people know the look and have a concept of what "Captain America" is, though this is actually somewhat problematic when selling the character/film (particularly outside the US), since perceptions of Cap are heavily linked to how you perceive America. The general public's image of Cap is a guy obnoxiously chanting "U-S-A!" and waving a "Four More Years of Bush" sign.
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