In America, the two parties select their candidates for President at their national conventions.
The Democratic National Convention this year will be held in Philadelphia on July 25th to 28th. The Republican National Convention will be held in Cleveland, between July 18th to 21st.
It is at the conventions that state delegates pledge themselves to a candidate. Conventionally, if candidate has a majority of delegates then they are the party nominee. If no single candidate has a majority then there is a brokered convention, which can result in re-votes and trades to decide upon a nominee.
Primaries and Caucuses
Candidates in both parties must win delegates through state primaries and caucuses.
The two parties do this separately and have different rules and schedules. In broad terms, a state with a larger population will have more delegates to award. So, winning a large state like California will yield more delegates than a small state like Rhode Island.
The Democratic Party always awards delegates proportionally: the delegates of the state are divided proportionally to the vote share. The Republican Party has some ‘winner take all’ states, like Florida, where the winner takes all the delegates. Certain states also have minimum vote share to take delegates, conventionally between 10-20%. Candidates below these thresholds in these states do not win any delegates.
Most states use primaries, closed or open. In a closed primary only registered party members can participate in that party primary. In an open primary, registered voters can participate in either party’s primary, though he or she must select only one. The voter goes to a station, into a booth and casts their ballot.
Caucuses have decreased in popularity since the early twentieth century. Though states have varying rules on how they are conducted, a caucus is a far more public way of choosing delegates. Party members will meet in a public area, discuss and argue the merits of the nominees before having a public vote.
The General Election
Once both parties have their nominees, confirmed through the conventions, the race for the presidency begins.
Unlike the primaries and caucuses, all states go to the polls on the same day. This year, election day is November 8th. Voters do not directly vote for the nominee, but for the state’s electoral college, which they pledge themselves to their party’s nominee.
Whichever nominee has a majority of delegates wins the election and takes the keys to the White House. The magic number to reach is 270. Conventionally, most states lean one way or another: Texas goes Republican, New York goes Democrat. There are a handful of crucial swing states that are considered ‘purple’, somewhere between Democrat blue and Republican red. Ohio, Florida, Virginia and North Carolina have recently been key swing states.
Below is a map detailing how Barack Obama and the Democrats won in 2008.