Theodore Roosevelt Forms Bull Moose Party After GOP Convention Theft: Republican Split Ensures Wilson Victory

Theodore Roosevelt accepted the Progressive Party nomination for president at a convention in Chicago, formally splitting from the Republican Party after losing the nomination to his former friend William Howard Taft despite winning nine of twelve state primaries. Roosevelt’s “Bull Moose” candidacy—named after he boasted feeling “strong as a bull moose”—represented the most successful third-party presidential campaign in American history and a fundamental rupture in the Republican coalition between corporate conservatives and progressive reformers. In February 1912, Roosevelt had stunned the nation by challenging sitting President Taft, violating the unwritten rule against seeking a third term. Roosevelt took advantage of newly-established direct primaries, carrying nine states and securing significantly more delegates than Taft or Wisconsin Senator Robert La Follette. However, at the June Republican National Convention in Chicago, state party leaders still controlled the nomination system and delivered the nomination to Taft.

On the evening of June 22, 1912, Roosevelt asked his supporters to leave the Republican convention floor. Progressive Republicans reconvened at Chicago’s Orchestra Hall and endorsed formation of a national progressive party. The Progressive platform called for direct election of U.S. senators, women’s suffrage, tariff reduction, and sweeping social reforms including workers’ compensation, minimum wage laws, and regulation of corporations. The party attracted social reformers, labor advocates, and middle-class voters alienated by corporate control of the Republican establishment. In the November 1912 election, Roosevelt won 27.4 percent of the popular vote compared to Taft’s humiliating 23.2 percent—making Taft the only sitting president to finish third in a re-election bid. Roosevelt became the only third-party nominee to finish with a higher vote share than a major party nominee.

With the Republican vote split, Democrat Woodrow Wilson won handily with 41.8 percent of the popular vote and a vast electoral college majority. The Bull Moose Party collapsed in the 1914 midterms and died in 1916, but the Republican split delivered Wilson the presidency and enabled passage of the Federal Reserve Act (1913), Federal Trade Commission Act (1914), and Clayton Antitrust Act (1914). The episode revealed the vulnerability of progressive movements to institutional capture: even when reformers won primaries and popular support, party bosses aligned with corporate interests could override democratic outcomes through control of convention machinery. Roosevelt’s decision to leave the Republican Party, rather than continue fighting for its transformation, also demonstrated the limits of third-party challenges—the Progressive Party’s quick collapse showed that without capturing a major party’s infrastructure, reform movements face insurmountable structural barriers in America’s two-party system.