The United States has generally used a party system to elect its presidents and other governmental officials. For certain reasons these parties have become weaker over recent years. The main factor of this weakening has been reform efforts within the parties themselves. These reform efforts started in 1972 when the Democratic Party instilled a set of rules that were designed to regulate control over delegates and increase the numbers of minorities that were involved in the national nominating convention.
These rules worked as intended in the beginning. This is shown by the election of 1981 where 14% of the delegate seats were reserved for elected officials. Also, none of those people had to commit themselves to a presidential candidate. This is what the party had hoped the rules would do since they wanted the party to be a democracy within as well as outside. However, it was the constant changes in the rules that caused this original success to change into failure thus weakening the entire party.
If both parties would adapt rules that regulated the amount of each group that is represented at their national conventions then the selections would be more diverse thus reaching a greater amount of people. The whole idea of the selection process is to choose the right candidates that will get people to choose your party over the others that are running also. With more diverse people choosing the candidates that will represent a party than the candidates will be chosen from the people as a whole not just those so-called political elites.
With the selections of the parties being more in tuned with all the people of the nation then the parties will be much stronger and backed by everyone. Since it was all the reforms of the 80's that caused this...