Officers of the CongressThe Constitution provides that the vice president shall be president of the Senate. He or she has no vote, except in the case of a tie. The Senate chooses a president pro tempore to preside when the vice president is absent. The House of Representatives chooses its own presiding officer -- the speaker of the House. The speaker and the president pro tempore are always members of the political party with the largest representation in each house.
At the beginning of each new Congress, members of the political parties select floor leaders and other officials to manage the flow of proposed legislation. These officials, along with the presiding officers and committee chairmen, exercise strong influence over the making of laws.