>>hhjink+(OP)
It depends to what degree it's literal copying. See e.g. the Obama "Hope" poster. [1] Though that case is muddied by the fact that the artist lied about the source of his inspiration. Had it in fact been an older photo of JFK in a similar pose, there probably wouldn't have been a controversy.
[1] https://en.wikipedia.org/wiki/Barack_Obama_%22Hope%22_poster