Bob Toad is correct in his statement that voting in a party primary is not a right.  The Democratic Party, the Republican Party, the Libertarian Party, the Green Party, etc; they are by definition "parties," not mini-democracies.  They are private clubs that have formed to pull-together the resources of their members to put forward the man (or woman) of their choice to run in the general election.  There is nothing in the Constitution that constrains them to operate "democratically."  In fact, there is nothing in the Constitution about political parties at all.

In a way, we should be thankful that we have primary elections and causcuses at all.  Previously the party favorite was picked in the back rooms, not at the ballot boxes.  They could decide the party nominee by coin flip, or nude mud-wrestling match, if they desired.  The only reason why the major political parties have now partially embraced the concept of selecting party candidates by popular vote is because they sensed that if such a concession were not made -- to at least give the semblance of democracy -- then they risk a mass abandonment of the two party system and a disastrous loss of power.  Even still, as a firewall, they created the concept of superdelegates, to maintain at least partial control of the process in the event of close races (both the Democratic Party and the Republican Party have them).

There is an obvious potential pro of having superdelegates.  Let's say something akin to our two party system existed in pre-Nazi Germany, with superdelegates ultimately being necessary to give a candidate the final push for the party nomination.  Hitler most definitely would have the popular vote wrapped up, but the superdelegates might have recognized him for what he was and threw in with the Kaiser instead.  The democratic process in that case would not be followed, but the undemocratic course would, as a result, have been best for the party, and for Germany.  Superdelegates can theoretically be a check and balance against mob rule.  It won't be the first undemocratic process at play in our implementation of democracy.  The Senate was a specific construct of the Founding Fathers to protect us against mob rule (a body not simply answerable to the short-term wishes of the people, but also to the long-term interests of the country).  The Founding Fathers didn't trust the people with pure democracy.  In fact, they feared pure democracy.  Don't even get me started on the Electoral College.

This is not to say that I advocate the superdelegate solution to establish a veneer of democracy to the primaries, while still maintaining party insider control.  It is, fundamentally contradictory to the democratic process played out in the general election.  And at this point, if either party thwarts the will of the majority and picks the candidate with the minority popular vote, then that will certainly be the end of that party.  I don't have a quick and easy solution to this dilemma.  My long run solution would be to undermine the all-encompassing power of the two-party system, and to make it possible for candidates to be viable without receiving the blessing of, or emerging from, the two major political parties.  In my mind, that would be by instituting Instant Run-Off Voting, but that's a topic of another article.