The 2016 U.S. elections are here -- and these are some of the terms you'll hear as Americans cast ballots in presidential primaries and caucuses across the country.
Caucus: A type of meeting used by political parties to discuss various issues. A presidential caucus is a political meeting where participants indicate their preferred candidate for president and begin their state's process of selecting delegates to their party's national convention. Caucuses are usually the first stage in a multi-step process. One of two methods used to select delegates (other being a primary).
Delegates: Representatives elected in primaries and caucuses who will be responsible for choosing the presidential and vice-presidential nominees at the parties' national conventions.
Entrance poll: In the Iowa caucuses, this is the same as an "exit poll" (see below) except that caucus-goers are interviewed as they enter the caucus site, rather than when they leave it. As a result, in caucus states the correct term is "entrance poll," not "exit poll."
Exit poll: A survey of voters in states which hold primaries that is conducted throughout Election Day. It is called an "exit" poll because voters are interviewed as they exit from a polling place. Voters are asked who they voted for, as well as for certain personal characteristics, such as age, race and sex. (In states with a high number of absentee voters, telephone polls are also used to gather data on vote intention and personal characteristics and the results are then blended together with the interviews conducted on Election Day.)
Hybrid: An allocation method used by Republicans that combines aspects of other allocation methods, usually proportionality and winner-take-all.
Initial preference: In the Iowa Democratic caucuses — as well as in a few other Democratic caucus states — the point in which caucus-goers first indicate their top choice for president. Candidates who do not meet a required minimum level of support after caucus-goers indicate their initial preferences are eliminated from the process. (see also "pre-viability")
Non-binding primary (aka "beauty contest"): A primary that does not affect a party's delegate selection process. Voters cast ballots for their preferred candidates, but no delegates are allocated to candidates based on the results.
Pledged delegate: A delegate who pledges support or indicates his or her intent to support a certain presidential candidate at the national convention. However, these delegates are not required to support the candidates to whom they are pledged.
PLEO: Acronym in the Democratic delegate selection process for "party leaders and elected officials." This is a type of delegate position that is reserved for those who hold a party leadership position, or who hold an elected office. "Unpledged PLEOs" are also known as "superdelegates," who get to serve as a national convention delegate automatically as a function of the position they hold. "Pledged PLEOs" are local elected officials who must compete against each other for these reserved delegate slots.
Post-viability: Refers to the point in certain Democratic caucuses — including Iowa — when candidates with less than a specified level of support have been eliminated from the process, and their supporters have realigned themselves with other candidates.
Precinct caucuses: In Iowa, the first step of the state party's presidential delegate selection process. This year, the Iowa precinct caucuses will be held on Monday, February 1.
Pre-viability: Indicates the period in certain Democratic caucus states — including Iowa — before candidates with less than a specified level of support have been eliminated from the process, and their supporters have realigned themselves with other candidates.
Primary: An election in which voters choose from among candidates competing for a party's nomination. One of two methods used to select delegates (the other being a "caucus").
Proportional representation: A rule requiring that candidates are allotted delegates in proportion to the percentage of the popular vote they receive. The Democratic Party requires the use of proportional representation for all primaries and caucuses; the Republican Party does not.
RNC-member delegates: Shorthand for Republican National Committee members who automatically get to serve as delegates to the Republican National Convention. This term refers to a state-party chair, a state's national committeeman, and a state's national committeewoman. There are 168 RNC-member delegates (three from every state, each territory, and the District of Columbia). In most states, the RNC-member delegates are allocated to candidates the same way other statewide delegates are allocated. In 6 states and territories (American Samoa, Colorado, Guam, North Dakota, Virgin Islands, and Wyoming), the RNC-members are unpledged, meaning they can support whomever they choose.
State delegate equivalents: In the Iowa Democratic caucuses, the estimated number of delegates to the Iowa Democratic Party's state convention that a presidential candidate would eventually win, based on the results of the precinct caucuses. This number can then be used to estimate the number of national convention delegates each presidential candidate would eventually win, also based on the results of precinct caucuses. The Iowa Republican Party does not calculate state-delegate equivalents.
Superdelegates: Delegates to the Democratic National Convention who are guaranteed a delegate slot based on their position in the party, or on an elective office they hold. All members of Congress, Democratic governors and other key party leaders are automatically superdelegates. Also known as "unpledged delegates."
Threshold rule: A rule requiring candidates to receive a certain minimum percentage of support before they win any delegates, or advance to the next stage of the delegate selection process. The threshold is the percentage of the vote that a presidential candidate must receive in order to be included in the calculations for awarding delegates to presidential candidates. Any candidate in a Democratic caucus or primary — including Iowa and New Hampshire — receiving 15 percent of the vote will be given representation. The Republican Party has never enacted a mandatory threshold rule.
Trigger: Similar to a threshold, a trigger is a vote threshold that a candidate running in a proportional state has to reach in order to win all the delegates in that state. Triggers are usually set a 50% and are only used in Republican contests.
Unpledged delegate: See "superdelegate."
Viability threshold: A specified percentage of popular support a candidate must reach in order to be awarded delegates, or to advance to the next stage of the delegate selection process. The Democratic Party requires that presidential candidates receive at least 15% of the vote in order to be considered viable. Some state parties in the GOP utilize viability thresholds in the allocation of their delegates; others do not.
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Winner-take-all: A delegate allocation method used by Republicans in which the statewide winner of a contest wins all of the delegates at stake in that contest.