Why was teddy roosevelt upset enough with taft in 1912 to run against him for president

Yet Roosevelt also knew that if he did not run, the Republican Party might split between his loyal supporters and supporters of another candidate, and thus allow a non-Republican to win the election. To prevent this, he followed the advice of his political advisors and selected a successor, someone he could nominate at the upcoming Republican convention to please both his supporters and the traditional Republicans who valued Washington's precedence. He made sure that his long-time friend Senator Henry Cabot Lodge presided over the convention so that he could control the floor. The plan worked, and Roosevelt's faithful political ally William Howard Taft was nominated as the Republican presidential candidate. During Roosevelt's administrations, Taft had served as Governor of the Philippines and as Secretary of War. Taft won the rather uninteresting election of 1908 against the Democrats' third time nominee William Jennings Bryan, 321 electoral votes to 162.

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