The Committee on Appropriations holds the power of the purse, responsible for writing legislation that allocates federal funds to numerous government agencies, departments, and organizations. Its twelve subcommittees determine spending levels for discretionary programs across the government, after reviewing presidential budget requests and holding hearings.

The Committee on Armed Services exercises legislative oversight for the nation's military, including the Department of Defense, military research and development, nuclear energy activities, and benefits for members of the armed forces. It also handles the confirmation of presidential nominees for senior defense and military positions.

The Committee on Commerce, Science, and Transportation addresses a wide range of issues including interstate commerce, transportation systems, science and technology policy, space exploration, and consumer protection. It oversees agencies like the Department of Transportation, NASA, the FCC, and the FTC.

The Committee on Homeland Security and Governmental Affairs provides oversight of homeland security operations and the efficiency and management of the federal government. Its jurisdiction includes counterterrorism, cybersecurity, border security, emergency management, and governmental affairs, including the Postal Service and the Census Bureau.