總統競選期間，如果奧巴馬或者羅姆尼意外去世，那麼下面會是什麼樣的流程？

總統和總統候選人去世的意義是不同的。如果前者去世，由副總統繼任，美國歷史上已有8位，包括哈里森、林肯、肯尼迪等；如果後者去世，所在政黨將選出另一名候選人填補空缺，歷史上尚無先例。

Question

What happens to a U.S. presidential candidate if he/she dies after their respective political party grants them the nomination, and before they are elected? Are there bylaws set up by each individual party that provide procedures for this? Also, is there a historical precedent in U.S. history where this may have happened in the past?

Answer

No presidential candidate of a major party has ever died or withdrawn before a presidential election and no President-elect has ever died or withdrawn after winning the general election, but before taking office.

However, one vice-presidential candidate died after he was nominated, but before the general election, and another dropped off his party"s ticket.

The procedures for finding replacements for candidate vacancies are guided by federal and state laws and party regulations. They are not exactly a patchwork, but they have evolved in response to practical problems that have arisen during the presidential elections, and in response to the growth of political parties as integral players in the election process.

In this respect, the procedures for filling vacancies in the parties" nominated tickets are like those that have evolved for the succession of the presidency when the person holding that office vacates it for one reason or another: When William Henry Harrison contracted pneumonia after giving a three-hour-long speech in the snow at his 1841 inauguration and died barely a month later, he was succeeded in office by John Tyler. It was not until confronting the issues raised in the transition of power from Harrison to Tyler that Congress thought through the rules for the succession of the President when the office is vacated during mid-term.

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http://teachinghistory.org/history-content/ask-a-historian/20431