Proportional Representation in Presidential Elections
The Democratic Party uses proportional representation in its primaries and caucuses to
nominate presidential candidates. Any candidate who wins at least 15%
of the vote in a primary or at a caucus is entitled to a fair share of
delegates based on their share of the vote in that state. In a primary,
the vote is based on statewide totals. For caucuses like those in Iowa,
the threshold applies in each caucus, and participants may choose to
support a second choice candidate if their first choice is unlikely to
have enough support to elect a delegate. The Republican Party allocates delegates by full representation in some states like Iowa and New Hampshire, but in many states uses systems based on winner-take-all (whichever candidate finishes first taking all delegates) or winner-take-all by district.
In general elections, all states except Maine and Nebraska now allocate electors by winner-take-all based on the statewide vote: Maine and Nebraska allocate two electors to the statewide winner and one elector to the first-place finisher in each U.S. House district. In the past, some states allocated electoral votes by proportional representation.
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