No mention of an office of vice president was made at the 1787 Constitutional Convention until near the end, when an 11-member committee on "Leftover Business" proposed a method of electing the chief executive (president). Delegates had previously considered the selection of the Senate's presiding officer, deciding that, "The Senate shall choose its own President," and had agreed that this official would be designated the executive's immediate successor. They had also considered the mode of election of the executive but had not reached consensus. This all changed on September 4, when the committee recommended that the nation's chief executive be elected by an Electoral College, with each state having a number of presidential electors equal to the sum of that state's allocation of representatives and senators.
The proposed presidential election process called for each state to choose members of the electoral college, who would use their discretion to select the candidates they individually viewed as best qualified. Recognizing that loyalty to one's individual state outweighed loyalty to the new federation, the Constitution's framers assumed that individual electors would be inclined to choose a candidate from their own state (a so-called "favorite son" candidate) over one from another. So they created the office of vice president and required that electors vote for two candidates, requiring that at least one of their votes must be for a candidate from outside the elector's state, believing that this second vote could be cast for a candidate of national character. Additionally, to guard against the possibility that some electors might strategically throw away their second vote in order to bolster their favorite son's chance of winning, it was specified that the first runner-up presidential candidate would become vice president. Creating this new office imposed a political cost on strategically discarded electoral votes, incentivizing electors to make their choices for president without resort to electoral gamesmanship and to cast their second ballot accordingly.
The resultant method of electing the president and vice president, spelled out in Article II, Section 1, Clause 3, allocated to each state a number of electors equal to the combined total of its Senate and House of Representatives membership. Each elector was allowed to vote for two people for president (rather than for both president and vice president), but could not differentiate between their first and second choice for the presidency. The person receiving the greatest number of votes (provided that it was an absolute majority of the whole number of electors) would be president, while the individual who received the next largest number of votes became vice president. If there were a tie for first or for second place, or if no one won a majority of votes, the president and vice president would be selected by means of contingent elections protocols stated in the clause.
The emergence of political parties and nationally coordinated election campaigns during the 1790s (which the Constitution's framers had not contemplated) soon frustrated this original plan. In the election of 1796, Federalist John Adams won the presidency, but his bitter rival, Democratic-Republican Thomas Jefferson came second and became vice president. Thus, the president and vice president were from opposing parties; and Jefferson used the vice presidency to frustrate the president's policies. Then, four years later, in the election of 1800, Jefferson, and fellow Democratic-Republican Aaron Burr each received 73 electoral votes. In the contingent election that followed, Jefferson finally won on the 36th ballot, and Burr became vice president. Afterward, the system was overhauled through the Twelfth Amendment in time to be used in the 1804 election.