One thing Horatio Seymour made clear was that he was not running for President. He made it clear by saying not only he would not run but that he "must not be President." His party simply didn't care. And so, there he was on the ballot. In this three-part series we look at people not running for President, not knowing they were running, or in the case of Greeley unable to finish the run because, well, they were not alive. You'll find that not running for President (but announcing it) is almost as much a part of American political history as running for the office.

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