My first instinct was to go back to the dawn of modern mass media -- that is, TV. The first simulcra was perhaps based on John F. Kennedy. The 1960 presidential debate may show one layer of identity, as viewers felt that JFK was suave and handsome while Nixon was ... well ... not. Many, many layers of identity later, JFK is a national icon whose memory is undoubtedly more real (in the Lacanian sense) than the man himself was. Probably every national public figure since JFK has been the inspiration of these layers of "hyperreal identity."
I think this phenomenon is inextricably linked to another facet of postmodernism: the fact that culture encompasses everything. The difference between highbrow and lowbrow culture is strained under the postmodern gaze. Take a look at the video link posted above. Does that debate look more like a presidential debate of today, or more like a couple kids running for president of the senior class? Our definitions of what is highbrow and what is lowbrow have changed considerably since that era. Those definitions were even in flux at the time, with both presidential candidates trying to appear simultaneously approachable (lowbrow?) and intelligent (highbrow?). It had already been years, at this time, since the innovative (some might say crazy) postmodern explorations of artists -- and cultural trendsetters -- like Jackson Pollock and Yves Klein.
The motivation of these artists also has a peculiar link to politics -- "emphasis was on the action and expressive movement use to produce the work, rather than the system used to create the piece or the resulting composition's appearance." If we take appearance is a synonym for the real, this statement relates directly to politics -- not only 1960s politics, but also the politics of today. Emphasis is on who can deliver the best sound bite, who can be the most mainstream on the right issues, who cleans up nice or the camera -- all forms of movement and action. It's rare to see someone focus on the "system of creation" of modern politicians. Instead, they distract us by saying they can't be defined by a party platform. It's even rarer to see anyone pinned down to the real. Instead, politicians adjust to each particular situation, resulting in an identity that is mediated by only a particular audience -- an identity that may have no "recourse back to a real person."
Is it any wonder our political system is in its current situation? Trying to make sense of the whole situation is like trying to understand the meaning behind "Number 1, 1948." Even given appropriate clues, the polysemy of each of these products makes the task damn near impossible.