Final answer:
The president who won in the electoral college by one vote was Thomas Jefferson.
Step-by-step explanation:
The president who won in the electoral college by one vote was Thomas Jefferson. The election of 1800 between Thomas Jefferson and John Adams was closely contested and resulted in a tie between Jefferson and his running mate Aaron Burr, both receiving 73 electoral votes. The tie was eventually broken in the House of Representatives, where Jefferson won by one vote.
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