The Democratic Party is one of the two major contemporary political parties in the United States, along with the Republican Party. Tracing its heritage back to Thomas Jefferson and James Madison's Democratic-Republican Party, the modern-day Democratic Party was founded around 1828 by Andrew Jackson, making it the world's oldest active party.^[8]

The Democrats' dominant worldview was once socially conservative and fiscally classical liberalism, while, especially in the rural South, populism was its leading characteristic. In 1912, Theodore Roosevelt ran as a third-party candidate in the Progressive ("Bull Moose") Party, leading to a switch of political platforms between the Democratic and Republican Party and Woodrow Wilson being elected as the first fiscally progressive Democrat. Since Franklin D. Roosevelt and his New Deal coalition in the 1930s, the Democratic Party has also promoted a social-liberal platform,^[1] supporting social justice.^[9]

Today, the House Democratic caucus is composed mostly of progressives and centrists,^[6] with a smaller minority of conservative Democrats. The party's philosophy of modern liberalism advocates social and economic equality, along with the welfare state.^[10] It seeks to provide government intervention and regulation in the economy.^[11] These interventions, such as the introduction of social programs, support for labor unions, affordable college tuitions, moves toward universal health care and equal opportunity, consumer protection, and environmental protection form the core of the party's economic policy.^[10][12] The party has united with smaller left-wing regional parties throughout the country such as Farmer–Labor Party in Minnesota and the Nonpartisan League in North Dakota.