U.S. presidential nominating convention

The convention cycle begins with the Call to Convention. Usually issued about 18 months in advance, the Call is an invitation from the national party to the state and territory parties to convene to select a presidential nominee. It also sets out the number of delegates to be awarded to each, as well as the rules for the nomination process. The conventions are usually scheduled for four days of business, with the exception of the 1972 Republican and 2012 Democratic conventions, which were three days each. (The 2008 and 2012 Republican conventions were also three days each, but in each case was shortened from the scheduled four days due to weather issues).

There is no rule dictating the order of the conventions, but since 1956 the incumbent party has held its convention second. Between 1864 and 1952, the Democrats went second every year (except for 1888). In 1956, when Republican Dwight D. Eisenhower was the incumbent, the Democrats went first, and the party out of power has gone first ever since. (Between 1936 and 1952, the Democrats were the incumbent party and went second, but it is unclear whether they went second because they held the White House or because they had always gone second.) Since 1952, all major party conventions have been held in the months of July, August or (for the first time in 2004), early September. (Election laws in some states would likely prevent conventions from moving into mid-September). Between the middle of the 20th century and 2004, the two major party conventions were primarily scheduled about one month apart, often with the Summer Olympics in between so they did not have to compete for viewers. In 1996, both were held in August to accommodate the Atlanta Olympics in July, the last Summer Olympics to date to be played in the U.S. In 2000, both conventions preceded the Sydney Olympics in late September.

In 2008 and 2012, the Democratic and Republican conventions were moved to back-to-back weeks following the conclusion of the Olympics. One reason for these late conventions had to do with campaign finance laws, which allow the candidates to spend an unlimited amount of money before the convention, but forbid fundraising after the convention, in order for the parties to receive federal campaign funds. However, if Barack Obama's choice not to receive federal campaign funds for the 2008 general election is repeated in future elections, this reason for the late scheduling of conventions will no longer be valid. Another reason for the lateness of the conventions is due to the primary calendar, which ends in early June, and the political party's desire to turn the convention into a four-day tightly scripted political rally for their nominee, which just happens to have a roll call vote for President. This includes such logistics as where each delegation sits on the convention floor, the order of speeches, how the nominee wants to present him or herself, and allows time for any negotiations in regards to the running mate. Finally, the parties also did not want to schedule their conventions around the Olympics. One reason why the Democratic Party held its 2008 convention after the two-week-long Beijing Olympics was, according to them, to "maximize momentum for our Democratic ticket in the final months of the Presidential election". But moving the conventions later into early September led to conflicts with the National Football League's season kickoff game, which opens the season on the first Thursday of September. However, the NFL accommodated the conventions and moved its games to an earlier start time in 2008, and an earlier date in 2012.

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