In reference to John McCain. Specifically, McCain's recent odd behavior of suddenly leaning to the ultra-right-wing spectrum on issues that he was once considered rationally centrist about. His sudden unending and inextinquishable support for previous arch nemisis President George W. Bush.
Origin--From Kang and Kodos, the two aliens from the Simpsons. Specifically to the Halloween episode, where they assume the forms of then presidential candidates Bill Clinton and Bob Dole. The episode is famous for 'Bob Dole's line "It doesn't matter who you vote for! Your planet is doomed! DOOOMED!"
"McKang's at it again. Now he wants to amend the Constitution to ban gay marriage."
"Do you think Bush and McKang are shaking hands to share vital nutrients?"