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  Republican President William McKinley defeats Democratic William Jennings Bryan in the 1900 election.
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  William McKinley, the 25th President of the United States, was shot at the Pan-American Exposition in Buffalo, New York.
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  President Theodore Roosevelt had the Panama Canal built.
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  Republican President Theodore Roosevelt defeats Democratic Alton B. Parker in the 1904 election.
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  Republican William Howard Taft defeats Democratic William Jennings Bryan in the 1908 election.
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  Democrat Woodrow Wilson defeated Republican president Theodore Roosevelt and Republican president William Howard Taft.
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  World War I started after the assassination of Archduke Franz Ferdinand.
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  Democratic President Woodrow Wilson defeated Charles Evans Hughes, the Republican candidate.
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  America joins in on World War I.
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  World War I ended with an armistice.
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  The 19th Amendment was passed, allowing women the right to vote.
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  Republican Warren G. Harding defeated Democrat James M. Cox in the 1920 election.