The presidential election becomes official with the announcement from the Electoral College

The electoral votes having been ceremonially counted in the House of Representatives in a joint session of Congress, Vice-President John C. Breckinridge made the official announcement that Abraham Lincoln and Hannibal Hamlin "having received a majority of the whole number of electoral votes" had been duly elected as president and vice-president of the United States and would serve a four year term beginning on March 4, 1861.  (By John Osborne) 
Source Citation
Frank Moore, The Rebellion Record: A Diary of American Events, with Documents, Narratives, Illustrative Incidents, Poetry, Etc. (New York: G.P.Putnam, 1861), I: 31. 
    Date Certainty
    Exact
    Type
    Campaigns/Elections
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