Which president's election is considered the start of the modern political party system in America?

The election of Andrew Jackson in 1828 is widely regarded as the beginning of the modern political party system in the United States. Jackson's campaign marked a significant shift in political organization and strategy, fostering the development of the Democratic Party, which focused on appealing to a broader base of voters, including common men. This era introduced campaigning practices such as organized rallies, party platforms, and a more active engagement with the electorate, changing the way political parties interacted with their constituents.

Jackson's presidency also catalyzed the opposition movement that ultimately led to the creation of the Whig Party, establishing a more dynamic two-party system that continues to influence American politics today. His leadership style and the way he mobilized grassroots support transformed political norms and expectations, solidifying the foundation for contemporary party politics.