I believe the primaries are a wonderful idea in contrast to the caucus system on the basis that it allows for private voting without facing pressure in a caucus style meeting based on personal beliefs. I do however, see one major problem that the primary system is facing: Extremism in candidates.
If one looks at WHO participates in primaries, it is not a moderate Democrat or a moderate Republican. The voters who participate in primary elections tend to be those with the strongest conservative or strongest liberal values. This, in turn, forces the nomination of candidates who do not see eye to eye with the majority of Americans. Candidates are pressured to seem extra-conservative or extra-liberal during the primary season, and turn back against their statements during the general election season in the fall.
I challenge moderate Americans to pay more attention to candidates early in the race, particularly NOW. If you see someone who is moderate, agrees with you and you can agree with them, register for their party 30 days before your primary election or caucus, and vote for their nomination. Without concerned, responsible citizens, we will continue to have candidates elected that do not see eye to eye with the average American voter.