There are two basic types of Democratic convention delegates: pledged and unpledged. A candidate is eligible to win a share of the pledged delegates at stake in a state if he or she receives at least 15 percent of votes cast in a primary or the preferences expressed in a caucus, either in a congressional district or statewide. Individuals who are pledged delegates are "pledged" to support the candidate to whom they are allocated. There are expected to be approximately 4,051 pledged delegates at the 2016 convention. There are three categories of pledged delegates: congressional district delegates, at-large delegates and pledged party leader and elected officials (PLEO delegates).
Congressional district delegates are allocated proportionally based on the results of the primary or caucus in a congressional district. The number of district delegates that are apportioned to each congressional district is determined by the Democratic vote in each district in recent elections. At-large delegates are allocated proportionally based on the statewide results in the primary or caucus. Pledged party leaders and elected officials (PLEO delegates) are delegates by virtue of their office; PLEO delegates can include statewide elected officials, state legislators, local elected officials or party leaders. PLEO delegates are allocated proportionally based on the statewide results of the primary or caucus.
Candidates are only eligible to receive a share of the pledged delegates at stake—congressional district delegates, at-large delegates or PLEO delegates—if they win at least 15 percent of votes cast in a primary or the preferences expressed in a caucus. That standard is commonly referred to as the 15 percent threshold. In addition to pledged delegates, there are alternate delegates for each state, Washington, D.C., Puerto Rico, and the U.S. territories. Alternates attend the convention but do not vote unless a pledged delegate is unable to attend.
Unpledged delegates, often referred to as "superdelegates," are automatic delegates to the convention and are not required to pledge their support to a presidential candidate. Unpledged delegates are members of the Democratic National Committee, Democratic members of Congress, Democratic governors, or distinguished party leaders (such as former presidents or vice presidents). There are expected to be approximately 713 unpledged Democratic convention delegates in 2016. If an unpledged delegate is unable to attend the convention, an alternate delegate is not substituted as a replacement.
The Democratic National Committee sets the rules that determine the overall composition of pledged delegates in state delegations (including those from Washington, D.C., Puerto Rico, and the U.S. territories). Delegations must be equally divided between men and women. Each state must set specific goals for the number of pledged delegates who are African-Americans, Hispanics, Native Americans, and Asian Americans and Pacific Islanders. Also, states are required to conduct outreach efforts, such as recruitment and training, to groups that have traditionally been underrepresented in the political process because of their race, ethnicity, age, sexual orientation or disability.
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The Establishment doesnt always get what it wants. (or Hill would have won in '08)