In a mammoth essay in the New Yorker, George Packer charts the demise of the current conservative era of US politics. The "Sunbelt conservatism", shepherded by Nixon, that arose in the polarised 1960s has now fallen apart:
The fact that the least conservative, least divisive Republican in the 2008 race is the last one standing—despite being despised by significant voices on the right—shows how little life is left in the movement that Goldwater began, Nixon brought into power, Ronald Reagan gave mass appeal, Newt Gingrich radicalized, Tom DeLay criminalized, and Bush allowed to break into pieces.
As Packer points out, McCain "missed the sixties" and comes across to many Americans as a "pre-sixties" leader. His appeal to the centre may allow him to survive an epochal shift already under way.
