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(Wednesday, August 7, 1912, nearly 7:00 p.m. CST) — Delegates to the 1912 Progressive National Convention, meeting tonight at Chicago Coliseum in Chicago, nominated former President Theodore Roosevelt of New York for President of the United States by acclamation.

Angered at the renomination of President William Howard Taft over their candidate at the 1912 Republican National Convention, supporters of Roosevelt convened in Chicago. They endorsed the formation of a national progressive party.

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When formally launched that summer, the new Progressive Party acclaimed Roosevelt as its presidential nominee and Governor Hiram Johnson of California as his vice-presidential running mate (by acclamation).

Both Roosevelt and Johnson appeared together to accept their nominations.

When questioned by reporters, Roosevelt said he felt as strong as a “bull moose.” Henceforth known as the “Bull Moose Party”, the Progressives promised to increase federal regulation and protect the welfare of ordinary people.

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The Roosevelt-Johnson ticket would face the incumbent Republican ticket of President William H. Taft and Vice President James S. Sherman (nominated in June 1912) and the Democratic ticket of Governor Woodrow Wilson of New Jersey for president and Governor Thomas R. Marshall of Indiana for vice president (nominated in July 1912), in the 1912 United States presidential election.

With the Republican Party split between the followers of Taft and Roosevelt, the Democrats would win the U.S. presidency for the first time since 1892.