Political parties have similar goals to interest groups, but there is a fundamental difference between the two. Political parties exist with the main focus of getting candidates elected to office. This consumes a great deal of their time and energy and distinguishes them from interest groups, who only seek to influence policy.
Parties in the United States are distinctly different than most other nations. Political parties here are what we refer to as umbrella parties.
Umbrella parties are political parties made up of several smaller groups who merely have enough in common to work together. Umbrella organizations are heterogeneous entities that can accommodate people representing a broad spectrum of interests.
Both Democrats and Republicans work to achieve their party goals, but are made up of a variety of groups. Traditionally, the Democratic Party has been home to labor unions, and the Republican Party has accommodated business interests, although these relationships are not set in stone.
The groups within the parties often have conflicting views, and it's important to realize that in an umbrella party, it's acceptable for a person to not believe in all of the stated party positions.
Laborers from a steel workers' union might find it difficult to find themselves working with gay rights advocates, but the Democratic party sees that as acceptable to have differences in belief. When these groups pool their energy and resources, more can be accomplished. The same logic holds true for the Republicans.
To learn more, visit scalisecmhs.blogspot.com and catalog.flatworldknowledge.com.