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The deadlock in the presidential election of 1800 was caused by a tie in the amount of votes cast for the Republican president, Thomas Jefferson, and the the Republican vice president, Aaron Burr. Because the ballot did not differentiate between the vote for vice president and president, a tie occurred. This tie was resolved when the vote went to the House of Representatives. Although it was a tie in there as well, eventually some of the states who caused the tie decided to vote for Jefferson over Burr, calling him "the lesser of two evils".