How are members of Congress elected, and what advantages do incumbents hold?
Topic 5.9 Congressional Elections: explain how congressional elections work and the factors, including incumbency, that shape their outcomes.
A focused answer to AP US Government Topic 5.9: how congressional elections work, the power of incumbency, the effects of redistricting and gerrymandering, the difference between midterm and presidential-year elections, and how to use them in Concept Application and Argument Essay answers.
Reviewed by: AI editorial process; not yet individually human-reviewed
Have a quick question? Jump to the Q&A page
Jump to a section
What this topic is asking
Topic 5.9 covers congressional elections and what shapes their results, above all the incumbency advantage and the effects of redistricting and gerrymandering. The College Board wants you to explain why incumbents win so often.
How congressional elections work
- House. All 435 seats are up every two years, elected from single-member districts.
- Senate. Senators serve six-year terms, with about a third up every two years.
- District lines are redrawn after each decennial census through redistricting.
The incumbency advantage
Redistricting and gerrymandering
Why this matters for the exam
Topic 5.9 is a frequent Concept Application topic (explain the incumbency advantage) and Argument Essay topic (does incumbency harm democracy). It connects to congressional behavior and structure in Unit 2.
How this topic connects across the course
Congressional elections are the electoral foundation of everything Congress does in Unit 2. The incumbency advantage and safe, gerrymandered districts help explain congressional behavior (Topic 2.3): members who sit in safe seats face primary pressure from their party base more than general-election competition, which pushes toward partisanship and can deepen gridlock. So a question about why Congress behaves as it does often traces back to how its members are elected. Linking the two units, the election that produces a member and the behavior that member then displays, is a high-value synthesis.
The topic also connects to representation themes across the course. The incumbency advantage raises the question of whether elections still hold members accountable, which is the participation-side version of the consent-of-the-governed ideal from Unit 1. And gerrymandering ties back to civil rights, since the drawing of district lines has been a recurring equal-protection battleground. When an Argument Essay asks whether congressional elections serve democracy well, you can weigh the stability and experience incumbents bring against the loss of competition and accountability, drawing evidence from incumbency, redistricting, and the founding emphasis on responsiveness to the people.
Try this
Q1. Name three sources of the incumbency advantage. [Recall]
- Cue. Any three of name recognition, fundraising, casework, franking, and media attention.
Q2. Explain how gerrymandering can affect congressional elections. [Short explanation]
- Cue. Drawing district lines to favor a party or incumbent creates safe seats, reducing competition and protecting incumbents.
Exam-style practice questions
Practice questions written in the style of College Board exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
AP 2019 (style)3 marksA sitting member of Congress wins re-election easily despite low approval of Congress as a whole. A. Identify the advantage that helps explain this outcome. B. Explain one source of that advantage. C. Explain how redistricting can affect congressional elections.Show worked answer →
A Concept Application FRQ, 3 points (A, B, C).
A. Identify: the incumbency advantage.
B. Explain a source: incumbents benefit from name recognition, fundraising, casework for constituents, and franking (free mail).
C. Explain redistricting: redrawing district lines (gerrymandering) can create safe seats that protect incumbents and parties.
Markers reward naming the incumbency advantage and a concrete source.
AP 2021 (style)6 marksDevelop an argument about whether the incumbency advantage harms representative democracy. Use at least one piece of evidence from one of the following foundational documents: the Constitution of the United States or Federalist No. 10. Provide a defensible thesis, evidence and reasoning, and a response to an opposing perspective.Show worked answer →
An Argument Essay FRQ, 6-point rubric.
Thesis (1): e.g. "The incumbency advantage harms democracy by reducing competition and accountability."
Evidence (up to 3): incumbents' fundraising and name recognition; gerrymandered safe seats; Federalist No. 10 on responsiveness to the people.
Reasoning (1): explain how reduced competition weakens accountability.
Alternative perspective (1): concede that incumbents bring experience and constituent service, then argue competition matters more.
Related dot points
- Topic 5.8 Electing a President: explain the process of electing a president, including primaries, caucuses, the national conventions, and the Electoral College.
A focused answer to AP US Government Topic 5.8: the presidential election process from primaries and caucuses through conventions to the Electoral College, how electoral votes are allocated, the debate over the system, and how to use it in Concept Application and Argument Essay answers.
- Topic 5.10 Modern Campaigns: explain how modern campaigns are run, including the role of technology, data, and media.
A focused answer to AP US Government Topic 5.10: how modern campaigns use technology, data analytics, social media, and professional consultants, the rise of candidate-centered campaigns, the cost and length of campaigns, and how to use these ideas in Concept Application and Argument Essay answers.
- Topic 5.11 Campaign Finance: explain how campaign finance is regulated and how court decisions have shaped the role of money in elections.
A focused answer to AP US Government Topic 5.11: how campaign money is raised and regulated, PACs and Super PACs, the effect of Citizens United on independent spending, soft versus hard money, and how to use these ideas in Concept Application and Argument Essay answers.
- Topic 2.3 Congressional Behavior: explain how congressional behavior is influenced and constrained by election processes, partisanship, and divided government.
A focused answer to AP US Government Topic 2.3: how elections, gerrymandering, the trustee and delegate models, partisanship, divided government, and gridlock shape the behavior of members of Congress and the policies they produce.
- Topic 2.2 Structures, Powers, and Functions of Congress: explain how the structure, powers, and functions of both houses of Congress affect the policymaking process.
A focused answer to AP US Government Topic 2.2: the enumerated and implied powers of Congress, the committee system and leadership, the budget and lawmaking process, and the difference between mandatory and discretionary spending.
Sources & how we know this
- AP United States Government and Politics Course and Exam Description — College Board (2020)