In the Presidential election , Republican President Theodore Roosevelt defeated Democratic judge Alton Parker from New York . Parker , a conservative Bourbon Democrat , won the Democratic nomination on the first ballot , as former President Grover Cleveland and former presidential nominee William Jennings Bryan both declined to run . Roosevelt dominated both the popular vote and the electoral college , carrying every state outside the South . Roosevelt , who succeeded William McKinley after the latter was assassinated in 1901 , became the first vice president to succeed to the presidency and later win election to the presidency in his own right . The election also saw Florida hold the first ever presidential primary , although Florida delegates were not bound by the results of the primary
Democratic nomination
1904 Democratic National Convention
1904 United States elections