The Twelfth Amendment to the Constitution, adopted in 1804: required the electoral college to vote separately for president and vice president created a new federal judiciary system with John Marshall as Chief Justice of the United States institutionalized the two-party system in American politics established the sovereignty of the national government over the state governments

The Twelfth Amendment to the Constitution, adopted in 1804, required the Electoral College to vote separately for president and vicepresident.

Until then, the Electoral College indirectly elected the vice president of the United States: while the president obtained the majority of the electoral votes, the candidate who finished second acceded to the vice presidency. Thus, political disputes were generated because many times it could happen that these candidates did not have similar political plans, or even didn't belong to the same party. With the approval of this Amendment, the vice president moved to integrate the presidential ballot, with which the voters had to start choosing candidates for both positions, and not only for the presidency.

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