Republicans usually have a very set succession for presidential nominees. If you are the incumbent, you may be challenged in the primaries, but you will be renominated (Nixon '72, Ford '76, Reagan '84, G.H.W. Bush '92, G.W. Bush '04). If you are the incumbent vice president when the president is termed out, you will be nominated (Nixon '60, G.H.W. Bush '88). If the field is wide open (except for Goldwater '64), and you are the highest elected official, most persistent presidential candidate or political dynasty heir who is credible, you will be nominated (Nixon '68, Reagan '80, Bob Dole '96, G.W. Bush '00).

It's also helped to be a Nixon, Bush or Dole. Every Republican ticket since 1952 has had a representative of one of these families, except Goldwater / Miller, and now McCain / Palin (both headed by Arizona senators, coincidentally).

America's second party can't afford to keep throwing away a real geographic advantage in choosing its candidates if it ever wants to beat the GOP and win a clear, majority popular and Electoral College victory for the first time since 1976. With luck, both parties' abandonment of the South in choosing their presidential tickets will come out in a wash for 2008.