US Party structure & Organisation

US political parties differ from those in the UK in terms of leadership. This distinction is shaped by the separation of powers and federal structure of the US, as well as the broader political environment. The separation of powers means that the President, despite holding significant influence in the party and setting the political tone, is not the formal party leader. 

Each element of the party has its own designated leaders in Congress. For instance, in 2024, Mitch McConnell led the Republicans in the Senate, while Chuck Schumer led the Democrats. In the House, Nancy Pelosi headed the Democrats, with Mike Johnson as the House Republican leader. The President and the opposing party's nominee do not directly control party legislators in Congress. Despite ideological alignment, negotiation and persuasion play crucial roles due to the relative lack of party discipline. (Power without Persuasion: Ways around Congress ) This can result in presidents facing opposition from their own party members, as seen with Trump's struggles to pass healthcare reforms during his initial two years in office or Biden's opposition from with the Democrat party in Congress. Leadership within parties is largely informal and revolves around strong personalities. Trump's influence over the Republican Party stemmed from his substantial grassroots following and lawmakers' loyalty to him out of concern for potential primary challenges. Party leadership becomes less apparent and impactful when the party is not in control of the White House

Factors affecting voting in Congress .

It is often stated that the United States does not have two parties, but rather 100, consisting of 50 state Republican parties and 50 state Democrat parties. State parties operate with a certain level of independence and autonomy. For instance, in Minnesota, local Democrats participate under the Minnesota Democratic–Farmer–Labor Party, a result of a party merger in 1944. State parties are instrumental in coordinating primaries and have their organizational structures, although their involvement in candidate selection is minimal. Local parties typically do not officially endorse primary candidates, although key local party figures may endorse individuals during primaries. 

The Democratic National Committee (DNC) and the Republican National Committee (RNC) are national party entities primarily responsible for organizing the national convention that officially nominates the party's presidential candidate and formulating the party's national platform. However, their influence in national politics is limited, especially regarding candidate selection. Consequently, their chairs, currently Jaime Harrison (DNC) and Ronna McDaniel (RNC) in 2021, are not widely recognized figures in households or major political players. Apart from the DNC and RNC, there are four "Hill committees" focused on electing party members to Congress. These committees include the Democratic Congressional Campaign Committee (DCCC), National Republican Congressional Committee (NRCC), Democratic Senatorial Campaign Committee (DSCC), and National Republican Senatorial Committee (NRSC). Their main function is to coordinate campaigns and donors, guiding financial contributions from supporters to key seats or bolstering vulnerable incumbents. They also engage in advertising and campaigns, often targeting opponents in competitive races. For instance, before the 2020 Senate elections, the NRSC launched a billboard campaign in various states, adapting the Democrat candidate's name to suit each state. While these committees do not directly select candidates, they frequently support and assist promising contenders, particularly those navigating their initial national election.

When analyzing party organization, it's important to consider the presence of various loosely connected groups. These groups share similarities with pressure groups but are more overtly involved in party politics. For instance, the Democratic Socialists of America (DSA), an organization independent of official Democratic Party structures, has around 50,000 members and aims to help progressive Democrats win primaries. In 2018, two DSA-endorsed candidates, Rashida Tlaib and Alexandria Ocasio-Cortez, were elected to the House. Similarly, on the Republican side, there's the Tea Party movement, which encompasses conservative, populist, and libertarian views. It's crucial to recognize the combined influence of central party structures, affiliated groups, and donors. For example, August 2022, the defeat of Liz Cheney who paid the price for her staunch opposition to Donald Trump’s assault on American democracy by losing her seat in Congress to a challenger backed by the former president. The vice-chair of the January 6 committee was beaten by a conservative lawyer, Harriet Hageman – who has echoed Trump’s false claims of widespread voter fraud – in a Republican primary election to decide Wyoming’s lone member in the House of Representatives.

Conceding defeat in a speech in Jackson, she said: “Two years ago, I won this primary with 73% of the vote. I could easily have done the same again. The path was clear, but it would have required that I go along with President Trump’s lie about the 2020 election.'

This incident demonstrated how primaries can be used to select and de-select candidates and further evidence of the grip Trump has on the Republican Party. Factionalism, referring to competing groups within a party seeking power and influence, is a key concept. These diverse groups, committees, and organizations showcase the unity within the diversity model of modern US parties, all aiming to secure election victories for their respective parties through various avenues of support.