premise: Thomas Jefferson helped to organize the Democratic-Republican Party in 1790.
hypothesis: The Democratic-Republican Party was an American political party formed by Thomas Jefferson and James Madison in 1791 -- 93 to oppose the centralizing policies of the new Federalist Party run by Alexander Hamilton , who was then Secretary of the Treasury and chief architect of George Washington 's administration . They included Thomas Jefferson ( nominated 1796 ; elected 1800 -- 01 , 1804 ) , James Madison ( 1808 , 1812 ) , and James Monroe ( 1816 , 1820 ) . Thomas Jefferson ( April 13 [ O.S. April 2 ] 1743 -- July 4 , 1826 ) was an American Founding Father who was the principal author of the Declaration of Independence and later served as the third President of the United States from 1801 to 1809 . Jefferson and James Madison organized the Democratic-Republican Party to oppose the Federalist Party during the formation of the First Party System .