The Structure of Congress (Edexcel A Level Politics): Revision Note

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The bicameral nature of Congress

• Congress is a bicameral legislature, meaning it is made up of two chambers: the House of Representatives and the Senate

• This structure is designed to balance popular representation with state representation and to prevent the concentration of power in one branch of government

The House of Representatives

• Contains 435 voting members

• Also has non-voting members, such as the representative for Washington DC

  • These members can take part in debates but cannot vote

• Each member represents a congressional district of roughly equal population

  • Every state must have at least one member

• Constitutional requirements:

  • at least 25 years old

  • a US citizen for seven years

• Holds exclusive powers, including:

  • initiating money bills (the power of the purse)

  • beginning impeachment proceedings

• Intended to represent the people of the US

The Senate

• Contains 100 members

• Each state has two senators, regardless of population

• Constitutional requirements:

  • at least 30 years old

  • a US citizen for nine years

• Holds exclusive powers, including:

  • ratifying treaties

  • confirming executive and judicial appointments

• Intended to represent the wider interests of the states

Concurrent powers of Congress

• Although Congress consists of two houses, many of its powers are concurrent, meaning they are exercised together

  • Both chambers:

    • pass, amend and suggest legislation

    • are required to overturn a presidential veto by a two-thirds vote

    • are required to propose a constitutional amendment by a two-thirds vote

Membership of Congress

• Congress reflects two different democratic principles: proportional representation in the House and equal state representation in the Senate

Representation and composition

• Demographically, Congress does not fully reflect the population. In the 119th Congress (2025–27):

  • 96% of members had a four-year college degree, compared to around one-third of Americans

  • 155 (29%) women held seats in Congress, compared to just over 50% of Americans

  • 61 (11%) African Americans held seats in Congress, compared to 14% of Americans

  • 56 Hispanics held 10% of seats in Congress, compared to 20% of Americans

• Members of Congress may represent multiple interests simultaneously, including:

  • their constituents from their state or district

  • party leadership

  • ideological caucuses

  • personal beliefs

The Congress election cycle

• Congressional elections use the First Past the Post electoral system and take place every two years

  • All House seats are contested every two years

  • One-third of Senate seats are contested every two years

    • Senators serve six-year terms

The election timeline

Fundraising and incumbency

• Campaigns rely heavily on:

  • individual donations

  • PACs

  • Super PACs

• In 2020 and 2022, candidates spent over $8 billion

• Incumbents have significant advantages:

  • name recognition

  • stronger donor networks

  • access to official congressional resources

  • potential protection from gerrymandered districts

• Turnout in congressional elections, especially midterms, is low

  • This further benefits incumbents

Distribution of powers in Congress

• Congress has three key functions, which shape how power operates within the institution

Key functions of Congress

• There is debate over whether the House of Representatives or the Senate is the more powerful chamber, or whether power is balanced between them

Who is more powerful?

Arguments that the House and Senate are equal in power

• Many of the powers of Congress are concurrent, meaning they are exercised jointly by both chambers

  • Both chambers must approve legislation before it can be sent to the President for signature

  • Both chambers must achieve a two-thirds majority to overturn a presidential veto

  • Both chambers use committees and investigations to conduct oversight of the executive branch

  • Both chambers must achieve a two-thirds majority to propose a constitutional amendment