The 26th President's belief in rugged individualism extended to his own political career. Two years after finishing his second term as President, Roosevelt announced his candidacy for a third in 1911. After incumbent William Howard Taft won the Republican nomination, Roosevelt struck out on his own to form the Progressive Party, better known as the Bull Moose Party after Roosevelt's boast to reporters that he was "as strong as a bull moose." Roosevelt wasn't strong enough to win the election, losing to Democrat Woodrow Wilson, though he did outdraw Taft in the popular vote. Nonetheless, his run siphoned enough progressives away from the GOP to give the party a distinctly more conservative feel in the ensuing years.
The Crist Switch: Top 10 Political Defections
Florida Governor Charlie Crist announced April 29 that he will leave the Republican Primary and run for the U.S. Senate as an independent. He is not the first to change sides. Over the years, scores of politicians have danced from one side of the aisle to the other. TIME rounds up the top 10 political defections in U.S. history