9. Obama Hope by Shepard Fairey, 2008

Though it might be argued this work is simply political by subtext, there's no mistaking the two-toned image above the word HOPE that became synonymous with the historic election of Barack Obama. It was eventually adopted officially by his campaign. Fairey's work in street art had been vaguely political at least figuratively up to that point, but his naivete in the endorsement of the then-democratic senator from Illinois verged on the propaganda, or perhaps that was the point. Though the AP has claimed rights to the image, it is known the world over, appearing on T-Shirts and magnets and lunch boxes and tattoos and action figures as Obama's election swept the globe—abundantly merchandised, typical of pretty much every Shepard Fairey work.

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