In addition to the formal power to authorize spending, Congressional power is derived from expertise. The committee structure of Congress forces members to develop policy specialties and select committees that are relevant to district needs. The legislative process gives committees substantial influence over legislation.
Committees can stop legislation from reaching the floor.
Individual Senators can block legislation by filibuster. American political parties are decentralized, Congress is organized into many committees and subcommittees, and members have very diverse local constituencies. Congress therefore appears to be very fragmented. President Expectations . In addition to the formal role for the Executive outlined in the Constitution, there are informal expectations for Presidential performance.