NO constitutional provision or federal law says how American political parties should select their presidential candidates. The system has evolved almost by happenstance. Its processes, often contradictory and in some instances so convoluted that both lawyers and politicians are hard put to explain them, are a bewilderment of accretions. It is through a combination of primaries, party caucuses and state conventions that delegates to the national conventions are chosen.
This year, the whole un-system is being put to question by the critics of the "old politics," mostly Eugene McCarthy's dissidents, the now leaderless...