(Disclaimer: Of course age alone doesn't disqualify (or qualify) a person from being President of the US.)
For an alternative, one could consider voting for John McClane for President, not John McCain. McClane's track record speaks for itself:
*In 1988, John McClane defused the hostage crisis at Los Angeles' Nakatomi Tower.(Via Neatorama.)
*In 1990, John McClane foiled a terrorist plot to seize control of Dulles International Airport in Washington, DC.
*In 1995, John McClane foiled the New York Federal Reserve Heist.
*In 2007, John McClane stopped the greatest cyberterrorism conspiracy in history.
*John McClane has defeated terrorists in elevator shafts on numerous occasions.
John McClane will keep us safe from terrorists, like he always has. A tough man for tough times. Yippie-Kay-Yay...